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Show 1905.] ABNORMAL RANTD LARV7E. 61 the corresponding bone on the right. A distorted fragment of cartilage in the muscles of the belly near the inferior termination of the left ilium represents the os pubis ; but I can find no trace of the remainder of the pelvic girdle or of the skeleton of either leg. The skeleton in B seems to have been entirely cartilaginous and is so distorted that no satisfactory account of it can be given. I can find no trace of the pelvic girdle or the hind limbs. The fore limbs in A are well developed but not symmetrical. The right hand, measured from the wrist to the tip of the 3rd (morphologically the 4th) finger, is 17 mm. long; the left only 15 mm. Otherwise the limbs appear to be normal. The pectoral girdle is naturally to a great extent cartilaginous. In abnormal larvae of the kind it is difficult to know what stage of development to expect in any given organ or structure ; but, on the whole, I do not think that this girdle is so advanced in development as the condition of the arms and of the first seven vertebrae would lead one to expect. It is quite symmetrical and not remarkable in any other respect. In B the fore limbs lay on the chest beneath the skin, which had ruptured in the region of either hand. I do not think that the spiracle had persisted, and both of the apertures may have been posthumous or of traumatic origin. The arms were readily freed by cutting through the skin. The measurements of them given above were taken after this had been done. Their bones appear to be more fully ossified than those of the remainder of the skeleton. To sum u p :-These two tadpoles, evidently belonging to the same species and possibly taken together, are abnormal in the absence of the hind limbs and, in at least one case, in the partial suppression, distortion, and asymmetry of the pelvic girdle. In the same specimen there is a less remarkable deformity of the fore limbs and the cranium is in an extremely primitive condition. The drawings for the Plate have been prepared under my supervision by Babu A. C. Chowdhary, to whose accuracy I am indebted. No attempt has been made to depict the specimens in a natural condition ; they are represented as they were found in the Museum. The bodies are shrivelled and distorted, and probably the fin-membranes, at any rate in B, were more extensive during life. The ventral integument in this specimen is torn, and I cannot locate the position of the vent with certainty. E X P L AN A T IO N OF PLATE V I . Abnormal larvae of Hana alticola. Figs. 1 ,1 a . A from tlie right side and below. Natural size. Figs. 1 h, 1 c. Cranium of A from above and below. Natural size. Fia;. 1 e- 8th and 9th vertebrae of A from above. X 4. Fig. I f . Do. from left side, with left ilium in natural position. X 2. Fig. 1 g. Do. from right side. X 4. Figs. 1 '/>, 1 j . Left ilium of A. X 2. Figs. 2, 2 a. B from the right side and below. Natural size. Fig. 2 b. Arms of B dissected out. Natural size. |