516 Mr. W. B. Bawkins on Ovibos moscbatus. [May 23, 



the action of water on P (JN" H^)^ CI O that had been exposed to heat, 

 and i)robably converted into P^ (N H,)^ Cl^ O^. If this hexamide really 

 exist, it is at once broken down by the freed hydrochloric acid, or by 

 hydrate of potassium, thus — 



^4 (NHJ, 0,H-H C1=]N-H,C1+P,N,H3 0„ 



giving rise naturally to a monobasic acid. 



If we regard the compound resulting from the action of nitrate of 

 silver on this acid as containing imidogen H, instead of amidogen 

 N H^, it gives a formula of great symmetry of structure — 



P(]N-H)AgOl ^ 



P(Vh) Ago 1 ^ - P.(NHXAg,0„ 

 P(NH) OJ J 

 and the salt would bear the name of tetra^lios^lio-tetrimate of silver. 



III. Ovibos woschatus (Blainville) .^^ By W. Boyd Dawkins, 

 M.A., P.G.S. Communicated by Prof. Huxley. BeceivedMay 

 9, 1867. 



(Abstract.) 



Ovihos moscliafus, more commonly known as the musk-ox, has been 

 described under different names by naturalists as their opinions fluc- 

 tuated concerning its affinities with the ox, buffalo, or sheep. It is 

 called the musk-ox by all the arctic explorers, Bos moschatus by Schre- 

 ber, Zimmermann, Pennant, and Cuvier, musk-buffalo allied to the 

 JBubalus Caffir of South Africa by Professor Owen, Ovibos onoscJiaivs 

 by Pe Blainviile, Desmarest, Eichardson, and M. Lartet. That the 

 latter four naturalists are right in the place they assign to it in the 

 zoological scale, intermediate between Ovis and Bos, is proved both by 

 the natural history and tlie osteology of the animal. The absence of a 

 muffle and dewlap, the hairiness of the nostrils, the shortness of tail and 

 smallness of ear, and the possession of tv/o teats only, separate the 

 animal from Bos and connect it with Ovis, while the large size and long 

 gestation of nine months difierentiate it from the latter animal. Precisely 

 the same evidence is afforded by its skeleton. In the skull, the taper- 

 ing of the anterior portion, the prominence of the orbit, the verticality 

 of the facial plate of the maxillary, the presence of a larmier, the square- 

 ness of the basisphenoid, the presence of the occipito-parietal suture on 

 the coronal surface ; in the dentition, the sharpness of the costse 1,2, and 3, 

 and the absence of the accessor}^ column from the inner interspace of 

 the lobes of the upper teeth are among the chief ovine characters, and 

 throughout the skeleton the same ovine tendency is manifested. With 

 the exception of the great development of hornS; there is no point in 



