OCR Text |
Show 1901.] ON BATRACHIANS AND REPTILES FROM SOMALILAND. 47 von einander zu trennen, bis sie endlich in eine mehr bliitterigte als fa'-erigte, feste und hornartige homogene, ein paar Linien dicke Schicht verschmelzen, die dann noch mit einer diinnen, aber ihr ahnlichen Oberhautschicht bedeckt ist." And Leydig \ from whose paper the above extract is quoted, himself observes :-" Betrachtet man endlich die freie Flache der Hornschicht vom AVallfisch, so unterscheidet das unbewaffnete Auge kleine scharf abgegrenzte Flecken, die mikroskopisch angesehen sich als besonders geartete Epidermispartien kund geben, indem sie von den gewohnlichen Epidermiszellen genau umschriebene Haufen eigenthumlicher rundlicher, mit concentrischen Eingen versehener Zellen darstellen. So viel ich gesehen habe, entsprechen diese Flecken den Stelleu, wo die Spitzen der Lederhautpapillen liegen." The "bonnet" of the Southern Eight Whale would thus appear to be but a circumscribed tract of skin, where, for some reason not yet apparent, the cornified layers fail to rub off at their normal rate, hut remain and accumulate to produce a hard mass, projecting above the general surface of the epidermis as a kind of corn. EXPLANATION OF PLATE VI. Fig. 1. Upper surface of the horny excrescence or " bonnet" of the Southern Bight Whale (Baleena australis). Two-sevenths natural size. Fig. 2. Side view of the same structure. Fig. 3. Section of the same structure, taken parallel to the cutaneous surface and at right angles to the cuticular fibres. (x30.) Fig. 4. Section of the nasal horn of Ehinoceros indicus, taken at right angles to the axis and about halfway up the horn. (X16.) Fig. 5. Section of the front part of the hoof of the Horse, taken halfway up and at right angles to the cuticular striations. (x 30.) Fig. 6. Section of one of the baleen-plates of the Southern Right Whale (Baleena australis), taken at right angles to the axis and about one-fourth of the total length from the point. (X 16.) 3. A List of the Batrachians and Reptiles obtained by Dr. Donaldson Smith in Somaliland in 1899. By G. A. BOULENGER, F.R.S. [Received December 23, 1900.] (Plate VII2.) The following list refers to a small collection made by Dr. Donaldson Smith on behalf of H.H. the Gaikwar of Baroda, to whose generosity the British Museum is indebted for a selected series of specimens, including the types of the new species here described. The specimens were obtained in January and February at three localities south and south-west of Berbera :-Biji, Ania, and Gan Lebar (altitude 5900 feet). 1 L. c. p. 681. 2 For an explanation of the Plate see p. 4 |