M. P. Gervais on the Freshwater Fishes of Algeria. 131 which acts as a "He-beam^* to a portion of the arch, and without much expenditure of force supports the weight of the body placed on the vertex of the straddhng arch formed by the tail and hind feet. I do not know of any other animal in which the quadratus femoris is inserted so low down on the femur, nor of any in which, as in the kangaroo, a special trochanter is provided for the insertion of this muscle. Its weight is In the Giant Kangaroo \'47 oz. In the Wallaby 0-91 „ The relative moment of the quadratus femoris in man,' the Quadrumana, and the kangaroos may be seen from the following comparison : in all cases the total weights of the hip-joint muscles being called 100, the quadratus femoris forms of the hip-joint muscles In Man 1 -25 per cent. In the Chaema 3*01 „ „ Green Monkey 3*00 „ „ Macaque 4*01 „ „ Wallaby Kangaroo 5*06 „ „ Giant Kangaroo 3*77 „ XXIV. — On the Freshwater Fishes of Algeria. By Paul Gervais*. In a memoir published as long ago as the year 1853 f, I gave some descriptive details of the fishes which had then been col-lected in Algeria in the different streams and in some lakes of that country, and showed how little they varied specifically. Including Coptodus and Tellia, both differing generically from European fishes, the number amounted only to seven, namely, Coptodus Zilliij a species of Tilapia ; Zillia apoda, of the family of Ci/prinodontes ; a Bleak [Leuciscus callensis, Guichenot); three Barbels, one of which even is contestable {Barbus callensis, Val., B. setivimensis, Val., and B. longiceps ?, Val.) ; lastly, an Eel, to which M. Guichenot also thought it necessary to give a specific name [Anguilla callensis). This list has since been increased only by two interesting species, a Trout (Salar macrostigma, A. Dum^ril J) and a Cyprinodon (C. duliatus and cganogaster, * Translated by W. S. Dallas, F.L.S., &c.,from the * Comptes Rendus,* I7th December 1866, pp. 1051-1058. t Bull. Soc. d'Agric de I'Herault, xl. p. 7G; Ann. des Sci. Nat. 3« serie, xix. X Revue et Magasin de Zoologie, 1858, p. 396, pi. 10.
BioStor
