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ing along the whole length of its back, and another from the vent to the tail-fin. Its broad mouth is surrounded by eight long barbels, and the fins at the throat (pectorals) are armed with a spine. It lives on the bottom, lying concealed in muddy places overgrown with weeds, and watching for its prey, which chiefly consists in other small fishes; thus resembling much the eel in habit, as in appearThe longest example of the Holy Land species, which I have seen, is about twenty inches long, but probably it grows to a much larger size, as African examples with a head twelve inches long are by no means rare. The Clarias appears to be a common fish in the Lake of Galilee, but is certainly one of those which the Jews were forbidden to eat by the Mosaic law.

ance.

Wherever in Africa the Clarias is found, it is accompanied by a fish of very different appearance, viz., CHROMIS and the kinds allied to it; and singularly enough, we find these two fishes also associated in the Holy Land. Otherwise, these Chromids are an exclusively African form, and there is no European fish to which they could be compared except, in some respects, the Perches. Like these, they belong to that great division of fishes which have the anterior part of the fin on the back composed of a series of spines, and the posterior of soft flexible rays; but the Chromids have that peculiarity that the line of pores on the side of the fish (lateral line) is not continuous, but interrupted on the posterior part of its course. They are broad fishes of an oval form, shaped somewhat in the manner of a Carp, with large scales. They swim in shoals, feeding on vegetable and animal substances, and must be the best eating fishes of the country, being esteemed as food in Egypt and other parts of Africa. The largest specimens I have seen did not exceed a weight of three pounds. Four or five distinct species are found in the Lake of Galilee and Jordan, belonging to two genera: a. Chromis includes the species in which the teeth of jaws are distinctly lobed.

1. Chromis nilotica has sixteen spines in the dorsal fin, and twelve or thirteen flexible rays; the front series of teeth in the upper jaw contains about seventy teeth; therefore, the teeth are very small.

2. Chromis simonis has fifteen spines in the dorsal fin, and only ten flexible rays; the lower jaw projects beyond the upper; the front series of teeth in the upper jaw contains about seventy teeth; therefore, the teeth are quite as small as in the preceding species.

3. Chromis andreæ.-The dorsal fin is composed of fifteen spines and twelve flexible rays. The teeth are much larger than in the two

other species, there being only forty or forty-six in the front series of the upper jaw.

b. HEMICHROMIS have been called those species in which the teeth are simply conical and pointed, without lateral lobes or notches.

[graphic]

By this character as well as by the presence of only fourteen spines in the dorsal fin, this fish may be readily distinguished from the others.

BLENNY.-I have made above some remarks with regard to its occurrence in Palestine; and I may abstain from adding descriptive notes, as the fishes of this genus are known to everybody. It is to be hoped that future researches will confirm or disprove its existence in the Lake of Galilee.

Small as the fish-fauna of Palestine is, it presents points of particular interest with regard to its affinities to other parts of the Old World. The Old World Faunas are of three principal types, viz., the (temperate) Europeo-Asiatic (Palæarctic), the Indian and African (which are tropical). From the central position of Palestine between these three faunas we might have drawn the inference that affinities to at least two of them would present themselves, but we would not have been prepared to meet with so intimate a connection of these three most diversified faunas. The Blenny, the three Cyprinodonts, the long-snouted Barbel, and the Eel are forms of decidedly European type. The Indian type is represented by a Discognathus, identical with a species from tropical India. But most remarkable is the close affinity to the fauna of tropical Africa, which here has its northernmost limits,* yet is represented in the Jordan by three Chromids, one Hemichromis, and one Clarias, two

I am well aware of the presence of a Clarias in the Orontes, which river, in fact, belongs to the same fauna as the Jordan, and, moreover, is inhabited by a Mastacembelus, another truly Indian form, which might also turn up in the Jordan.

of them being specifically identical with fishes from the Nile. So close an affinity appears to indicate that these two river-systems were connected at a former period, at a time when the present fish-fauna was already in existence.

Besides the fishes which may be regarded as representatives of extra-Palestinine types, there remain those which are peculiar to the Holy Land Fauna, or rather to what we may term the Syrian Fauna (including Mesopotamia), viz., Capoëta and Acanthobrama. Taking into consideration genera only, the proportions of the Syrian, European, African, and Indian types may be expressed by the numbers 5: 5: 4:3,-several of the genera being common to two or three of the faunas.

Much still remains to be done in the ichthyology of the Holy Land. Future researches will probably bring to light twice as many species as we know at present. There are many fishes, especially of the Siluroid and Cyprinoid kind, which live a retired life, or which are so scarce or local, that those only will be rewarded by their discovery who are enabled to stay in the country for some time. When we consider that a trout is found in the torrents coming down from the Atlas, another on Mount Olympus, a third in the rivers of the Hindoo Koosh, we may well expect that the waters of the Lebanon are also inhabited by their Salmonoid. Finally, our present knowledge does not enable us to judge of the affinity or difference of the fish-faunas of the rivers running into the Mediterranean, and of those belonging to the system of the Jordan.

STEIN ON THE STENTORS.

(With a Tinted Plate.)

(Continued from p. 356.)

THE Stentor polymorphus is the commonest form of this interesting family. Stein thus gives its specific characters :-" Body attaining large dimensions; when fully outstretched, it is in front one-third as broad as it is long; commonly coloured a lively green by a rich distribution of chlorophyll globules throughout the colourless external layer, but not seldom colourless; nucleus a distinctlyjointed, rose-garland shaped band." S. Mülleri Stein regards as a scarcely distinct variety of polymorphus, as it is only distinguished

VOL. III.-NO. VI.

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from it by the absence of the chlorophyll globules, to which he does not assign any specific importance. S. polymorphus is found extensively in Europe and America. Fully stretched specimens are frequently 1-2""(? half a German line) long, that is about 1-24", one twenty-fourth of an English inch. The parenchyma of the body is of greater consistency than is cœruleus or Rösellii, and the changes of shape take place with less rapidity. Stein says that in this species he has not discovered the long bristles amongst the bodycilia mentioned in the former paper. The body-tissue is white, with sometimes a yellowish tint, but not blue. The tissue between the body stripes is often the seat of a more or less rich collection of chlorophyll granules, and though these are frequently wanting, they make a good distinctive character when they occur. From the middle of spring till autumn, these chlorophyll globules may be seen thick together, and they are then larger in size and darker in tint. In winter or early spring they are sparsely scattered, and of a pale, yellow-green colour, or entirely wanting. In summer, colourless forms are often seen amongst intense green ones, but in other respects, such as size and shape of nucleus, conforming closely to the typical green form, and in many localities specimens occur with scattered pale green granules passing gradually into the colourless forms. S. Mülleri is an absolutely unmaintainable species. The oesophagus of S. polymorphus is difficult to see from the thickness of the body and the presence of the chlorophyll granules. Indeed it can only be observed clearly in colourless specimens.

In the inner parenchyma we mostly find only round foodvacuoles of small dimensions, which are commonly filled with Euglena viridis, small green or colourless monads or diatoms, with occasional vorticella heads, but no large organisms.

On one occasion Stein found an individual containing two small round bodies filled with an immense number of curled and intertwisted threads. He thought he had discovered spermatic capsules, and attempted to isolate the creature for further examination, but lost it amongst some algæ. He says he has not seen the slightest trace of a "ring-canal" in connection with the contracted vesicle. The long canal is not visible throughout its length in fully outstretched individuals. It is commonly seen as a continuous channel in only half the body, as shown in Plate I., Fig. 1, g, above which it presents the appearance shown in Fig. 2, g' g'. In one specimen caught at the beginning of division, two colourless astasia were seen in the widened portion of the long canal, g, as shown in Fig. 2, x x. These objects were very lively, changed their form, and

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