634 PROF. FLOWER ON A TWO-HORNED RHINOCEROS. [Jlltie 4, 



Prof. Ray Lankester, M.A., F.R.S., read a memoir on the hearts 

 of Ceratodus, Protopterus, and Chimcera. The structure of the 

 conus arteriosus and its valves was more particularly described in 

 this paper. Owen and Hyrtl had shown that the conus of the 

 Dipnoans differed from that of cartilaginous fishes and Amphibians 

 in the fact that its walls were devoid of pocket-valves, and presented 

 instead a long spiral valve and a second short vertical valve. Dr. 

 Giinther, the only author who had described the heart of Ceratodtis, 

 showed that it possessed in the upper part of the arterial cone 

 pocket-valves, whilst the spiral valve was shortened so as to be 

 absent from this upper region. The possession of pocket-valves 

 served as a very important character to connect the Dipnoans and 

 the other fishes. 



Prof. Lankester now showed that in the lower part also of the arte- 

 rial cone of Ceratodus there were numerous small pocket-valves, in 

 addition to those in its upper part ; and further he showed that these 

 small pocket-valves (so called "ganoid valves ") were also present 

 in the lower part of the arterial cone of Protopterus, the African 

 Mud-fish, which had been generally supposed to be quite devoid of 

 this kind of valve. The basal fibro-cartilage of the floor of the heart 

 was described and compared in Ceratodus and Protopterus, and a pos- 

 sible rudiment of this remarkable structure pointed out in Ceratodus. 



This Paper will be published entire, with illustrations, in the 

 Society's ' Transactions.' 



The following papers were read : — 



1. On the Skull of a Rhinoceros (R. lasiotis, Scl.?) from 

 India. By William Henry Flower, F.R.S., V.P.Z.S. 



[Eeceived October 12, 1877.] 



Mr. Sclater has put into my hands for examination the skull of a 

 Rhinoceros, which he had received from Dr. W. D. Stewart, of Cut- 

 tack, Orissa, being the skull of the two-homed Rhinoceros killed 

 near Comillah, in Tipperah, as mentioned in P. Z. S. 1877, p. 269. 

 Mr. Sclater thinks that the skull may not improbably belong 

 to the species (at present only known by the living animal in the 

 Society's menagerie) which he has named R. lasiotis. 



It is that of a nearly adult animal. All the sutures of the upper 

 surface of the cranium are consolidated ; and all the permanent teeth 

 in both jaws are in place except the posterior molars, which are still 

 concealed in their alveoli. 



In size and general conformation it resembles the skull of R. 

 sumatrensis, and possesses all the essential characters l which distin- 

 guish that species from R. indicus and R. sondaicus, viz. the sepa- 

 ration of the postglenoid from the posttympanic processes of the 

 squamosal below the auditory meatus, the backward position of the 

 occipital crest (though, perhaps, less marked than usual), and the 



1 See " On some Cranial and Dental Characters of the existing Species of 

 Bhinoceros," P, Z. S. 1876, p. 443. 



