Miscellaneous. 93 



On Nearctos and ^lurina. By Dr. J. E. Gray, F.R.S. tfec. 



Dr. Theodore Gill, in the ' Annals and Magazine of Natural 

 History ' for this year, xiii. p. 15, with his usual industry as a com- 

 piler, points out that I overlooked two generic names that have been 

 used by Gervais in his ' Hist. Nat. Mammiferes,' ii. 1855, Though 

 this book bears the date 1855, the second volume is not in the Mu- 

 seum Library, nor have I seen it in any other scientific or other 

 library in this country ; and being a history of Mammalia intended 

 only for popular use, it is scarcely a place in which a zoologist 

 would look for a new genus. 



Dr. GiU states that M. Gervais has established the genus Tre- 

 marctos on account of a " supracondyloid foramen of the humerus, 

 in which it is said to differ from all other Ursidoe;" but Dr. GiU 

 points out that this foramen is found in other Ursidae, and is doubt- 

 less exceptional and monstrous in them. I would ask, as only one 

 skeleton of Ursus ornatus is known, may it not be an individuality 

 in that specimen ? Certainly it is a novelty in zoology to establish 

 a genus on the existence or non-existence of a foramen in the 

 humerus. My genus Nearctos is established on the peculiarity in 

 the form of the lower jaw, shown to be a characteristic peculiarity 

 by the examination of several skulls, a true zoological character. 



In 18G7, I established the genus Viverriceps for Felis Bennettn 

 and several other Asiatic cats, because they have an elongate skull 

 and a complete bony orbit. I referred Felis planiceps to this genus, 

 because it had the same kind of skull — overlooking the peculiarity of 

 its having a compressed double-rooted first false grinder in the upper 

 jaw, which is figui*ed by De Blainville in his ' Osteographie,' and that 

 Professor Gervais had proposed the genus Ailurin (yEhirina) for 

 this animal in 1855 ; [and Fitzinger called it Ailurogale in 1869. . 



I have examined four skulls of this species and find that the pe- 

 culiarity of the false grinder is a permanent character of the species, 

 and therefore propose, as Dr. GiU has done, to retain both ^liirina 

 and Viverriceps. 



The front upper grinder of Viverriceps is subcyUndrical and one- 

 rooted, and differs in size !in different species. Thus, in Viverriceps 

 Bennettii it is smaU and conical ; in Viverriceps Ellioti it is very 

 small and rudimentary ; it is similar in V. rubiginosa, but very 

 soon falls out. 



On the Metamorphoses of the Acarina of the Families Sarcoptidae and 

 Gamasida^. By M. Megnij^. 



In July and August of last year I communicated to the Academy 

 two notes on the zoological position and physiological function of the 

 little parasitic Acarina referred to the genera Hypopus, Homopiis, 

 and Trichodacf;/lns, which, according to my observations, are merely 

 the heteromorjihous nymphs of certain Sarcoptida; — among others, of 

 the 'ryrotjlyphi. 



Since this period I have continued my investigations of the meta-r 



