to be sure, myriads of such forms, and if, in the present state of science, they can consistently be called by any name, I should prefer that of Zooids, or animal-like forms. They appear to me to be intermediate conditions of bodies, or a kind of stepping-stones, by means of which some future true animal is to reach its perfect form. Modern research in the class of Infusoria indicates that its component forms are of this kind, and therefore that this whole class is likely to be taken by the remaining classes of the Invertebrata, when more extended study shall have made us more familiar with their details. I would therefore insist that cell-processes, however closely interwoven they may be with the expressions of individual life, cannot be considered as constituting the ground-work of its definition. True individual animal life seems to involve a cycle of relations not implied in simple cells; in other words, these last must always lose their character as such, in a definite form which belongs to the individual. The true generative act involves conditions which are peculiar and quite distinct from any of the other physiological conditions of life; it must be regarded as resulting only from the conjugation of two opposite sexes, a sexual process where the potential representatives of two individuals are united for the evolution of one germ. The germ-power thus produced may be extended and branched by budding, &c., but it can be formed only by the act of generation; and the multiplication of animals by the processes of fission or of germination is of no higher physiological character than the mere segmentation of cells, or the reproduction of lost parts in the lower animals."

Professor Agassiz observed, that there was only an analogy between the segmentation of simple cells and the segmentation of the ovum, and went on to show the difference of the phenomena presented in the two cases.

As to the egg-like bunches, mentioned by Dr. Burnett as found in the bodies of the Aphides, and considered by him as "buds," and not as true "eggs," Professor Agassiz could not agree with him. From the absence of peduncles, these free cells had not the first characteristic of buds, and he was inclined to consider them rather as true eggs. He mentioned the instance of turtles, in which there are three kinds of eggs in different stages of fecundation or growth, some to be laid this

season, and others after a lapse of one or two years, which have received their fertilizing influence from the male this long period in advance. Speaking of the development of eggs, he alluded to the fact that in bees there are two kinds of females produced from eggs, which, in the beginning, present no differences; every female bee might become a queen if properly fed and cared for, but from want of the proper surrounding influences most of them become sterile. In some species of crabs, he had found also two kinds of females, fertile and sterile, though, unlike the bees, existing in about the same numbers.

Dr. B. A. Gould, Jr. made some remarks on the means of diminishing the personal equation, or the best method of getting rid of personal errors in transit observations made by different observers. He quoted M. Arago, from the Comptes Rendus for February 14, 1853, in which he claims priority for the method of employing the senses of sight and touch to diminish the personal equation, instead of sight and hearing, as usually employed; this method of tapping at the instant the star passed the threads of the instrument dates back to 1843.

Dr. Gould mentioned a similar method employed at Philadelphia, some time between 1828 and 1832. The best way, he believed, was that employed in our Coast Survey, by the electric clock, by breaking the circuit by a tap of the finger at the instant of the transit.

The problems, why sight and hearing should be less accurate than sight and touch, why observers should differ from each other, and why the same observer should differ from himself in the same manner of observation, are exceedingly difficult to solve; they involve the consideration of temperament, physiological conditions, state of the health, mechanical dexterity, &c., which make the subject exceedingly intricate.

Professor Bache, Professor Peirce, Professor Agassiz, and the President made remarks on the same subject.

Three hundred and eighty-second meeting.

August 10, 1853. — QUARTERLY MEETING.

The VICE-PRESIDENT in the chair.

The Corresponding Secretary read letters from Chevalier Bunsen and George Grote, Esq., acknowledging their election as Foreign Honorary Members of the Academy.

Dr. Gray called the attention of the Academy to the death of one of its Foreign Honorary Members, Adrien de Jussieu, of Paris, and made some remarks on the estimable character and eminent scientific services of this last representative of the illustrious line of the Jussieus.

Three hundred and eighty-third meeting.

September 28, 1853. ADJOURNED QUARTERLY MEETING. The PRESIDENT in the chair.

The Corresponding Secretary read letters from August Boeckh and R. Lepsius, of Berlin, acknowledging their election as Foreign Honorary Members of the Academy.

Professor Joseph Winlock, of Kentucky, now resident in Cambridge, and Rev. Thomas Hill, of Waltham, were elected Fellows of the Academy in the Section of Mathematics.

Dr. B. A. Gould, Jr. communicated to the Academy the fact, that there exists an error in the formula given in the blanks for the reduction of transit observations; and that all the observations in this country, and also the Greenwich observations, are incorrect by the amount of this error, the maximum of which amounts to one third of a second of time.

Professor A. Gray laid before the Academy a paper entitled "Characters of some new Genera of Plants, mostly from Polynesia, in the Collection of the United States Exploring Expedition, under Captain Wilkes." (In continuation of those communicated May 4, 1852; Proceedings, Vol. II. p. 323.)

DICLIDOCARPUS, Nov. Gen. Tiliacearum.

Flores polygamo-dioici? Calyx 3-bracteolatus, 5-phyllus; sepalis

crassis æstivatione valvatis. Petala 5, inappendiculata, æstivatione imbricata. Discus hypogynus, annularis, crenatus. Stamina creberrima, discreta antheræ biloculares. Ovarium sessile, oblongum, biloculare, pilis parcis circumdatum, stigmate sessili retuso coronatum, multiovulatum, fl. masc. effœtum sæpissime exovulatum. Capsula latissime obcordato-rhomboidea, bilocularis, disse pimento contrarie compressa, marginibus alata, ab apice loculicide bivalvis, polysperma. Semina lenticulari-globosa, hinc impressa, margine pilis prælongis crinita; testa fragili laxa. Embryo albumine carnoso vix brevior; cotyledonibus orbiculatis planis radicula æquilongis. - Arbor; foliis ovalibus integerrimis; stipulis caducis; floribus in cymulis axillaribus parvis.

DRAYTONIA, Nov. Gen. Ternstræmiacearum.

Calyx ebracteolatus, 5-partitus, imæ basi ovarii tantum accretus, persistens; sepalis inæqualibus æstivatione imbricatis. Petala 5, obovata, æstivatione convoluta vel convoluto-imbricata. Stamina plurima ; filamentis basi dilatatis breviter monadelphis: antheræ biloculares, dorso affixæ incumbentes, loculis apice rima introrsa hiantibus. Ovarium triloculare (rarius 4-5-loculare): stylus unicus: stigma obtuse trilobum. Ovula in placentis incrassatis, e loculorum angulo centrali prominentibus, plurima, anatropa. Capsula subcarnosa, trilocularis (rarius 4-5-locularis), apice loculicide trivalvis ? loculis polyspermis. Semina reticulato-scrobiculata. Embryo in axi albuminis carnosi, eodem dimidio brevior, subcylindricus; cotyledonibus brevibus semiteretibus. — Arbuscula Saurauja facie et affinis; sed differt, stylis in unicum coalitis, ovario triloculari ima basi calycis connato, disco nullo. DRAYTONIA RUBICUNDA. - Feejee Islands. The genus is dedicated to Mr. Joseph Drayton, the principal artist of the Expedition.

RHYTIDANDRA, Nov. Gen. Olacacearum.

Flores hermaphroditi. Calyx parvulus; tubo cum ovario connato; limbo cupulari truncato, margine 6-7-denticulato. Corollæ epigynæ petala 6-7, linearia, conniventia, æstivatione valvata. Stamina 6-7, petalis alterna, libera: filamenta brevissima, intus barbata: antheræ lineares, introrsum adnatæ, dithecæ, 4-locellatæ, locellis annulato

rugosis vel cameratis. Discus epigynus scutelliformis. Ovarium inferum, uniloculare, uniovulatum; ovulo ex apice loculi parvi suspenso. Stylus elongatus, sulcatus, bifidus, lobis 2-3-dentatis; stigmatibus terminalibus parvis. (Fructus ignotus.)- Frutex sarmentosus; foliis ovatis obliquis; pedunculis axillaribus cymulam paucifloram gerentibus. R. VITIENSIS. Feejee Islands.

PELEA, Nov. Gen. Rutacearum.

Flores polygami. Calyx 4-partitus, æstivatione imbricatus, cito deciduus. Petala 4, æstivatione valvata, mox decidua. Stamina 8. Discus brevissimus, integer, seu 8-crenulatus. Ovarium 4-loculare, 4-lobum, sæpius umbilicatum: stylus centralis: stigma 4-lobum. Ovula in loculis gemina. Capsula 4-partita stellariformis (coccis divaricatis), loculicida; endocarpio chartaceo ab exocarpio coriaceo seu lignescente solubili. Semina in loculis sæpissime bina, ovoidea; testa nitente drupacea. Embryo intra albumen carnosum rectus; cotyledonibus ovalibus; radicula supera. Arbores Sandwicenses inermæ, odoratæ ; foliis simplicibus integerrimis oppositis seu verticillatis coriaceis punctatis venosissimis ; floribus axillaribus. Genus Melicopi et Acronychia affine, Deæ Hawaiensium Pele dicatum. Species veræ Sandwicenses sex, septima dubia Samoensis. 1. P. CLUSIEFOLIA.

Clusia sessilis, Hook. & Arn. non Forst.

2. P. AURICULEFOLIA (sp. nov.): glabra; foliis ternis oblongospathulatis basi auriculatis sessilibus; floribus fasciculatis ad axillas foliorum delapsorum secus caulem virgatum brevissime pedicellatis; capsula quadripartita.

3. P. OBLONGIFOLIA (sp. nov.): foliis oppositis seu ovalibus petiolatis; pedunculis (fl. fert.) in axillis solitariis uni-bifloris petiolum adæquantibus; capsula quadriloba, coccis subcarinatis.

4. P. ROTUNDIFOLIA (sp. nov.): foliis orbiculatis sessilibus valde reticulatis; floribus cymulosis; calycis lobis ovatis petala subæquantibus; stylo ovario puberulo breviore.

5. P. SANDWICENSIS. - Brunellia Sandwicensis, Gaud. Bot. Freyc. 6. P. VOLCANICA (sp. nov.): ramis junioribus petiolis et inflorescentia cymuloso-paniculata hirsuto-tomentosis; foliis oppositis ovalibus longe petiolatis majusculis glabratis; calycis lobis ovatis petalis plus dimidio brevioribus; stylo gracili ovario tomentoso æquilongo; capsula (sesquipollicari) glabra quadriloba, coccis recurvis carinatis.