DE. J. AJfDERSOlSr OK AECTOMTS DIOHKOUS. 570 



and lays its eggs in the fluid which is caught there. I never 

 found it elsewhere ; but there it is extraordinarily abundant, and 

 every cabbage yielded ten or a dozen specimens. The fly creeps 

 in a slow, lazy manner. I am very sorry I did not observe whether 

 it climbs to the inflorescence in sunshiny weather ; perhaps this 

 may be the case. This is an instance of one of those " neglected 

 opportunities " to which you refer (in the ' Flora Antarctica ') as 

 so galling in the retrospect. Even at Heard [Yong] Island I 

 found the same apterous fly nestling on Fringlea in abundance. 

 Perhaps the two forms have some relation of mutual benefit." 



Note on Arctomys dichrous. By John Anuersox, M.D., F.L.S., &r. 



[Eead May 4, 1876.] 



(Plate XXXI.) 



In a preliminary notice on some new Asiatic Mammals and Chelonia, 

 published by me Jast year*, I very briefly referred to a few sjiecimens of 

 Marmot obtained in the mountainous country to the north of Kabul, and 

 which ap[)eared to me to oflFer pecuUarities entitling them to speciHc distinc- 

 tion. Since then my attention has been called to a paper by Mr. Blan- 

 fordf on the Marmots of the Himalayan range. I am induced, therefore, 

 to lay before the Linnean Society some additional memoranda on my spe- 

 cies Arctomys dichrous, and place at the disposal of the Council a figure 

 illustrating the animal in question. 



Mr. Blanford (/. c.) gives a succinct epitome of the history of the 

 nomenclature and synonymy of the Himalayan and Tibetan Marmots, and 

 expounds and criticises all the published data concerning the sui)posed 

 species from the above regions. A study of skins and skulls in the Indian 

 Museum, Calcutta, and some comparisons of other material incline him 

 to consider that there are four species, possibly a fifth (with that mentioned 

 hym3'self). Those best characterized he gives as under-mentioned, and he 

 suggests my A. dichrovs as probably the form indicated by Burns and 

 Griffith, while A. robustus, M.-Edw., he sinks in A. himalayanus, Hodg. 



Sect. I. Short- tailed Marmots, having the tail less than one third the 

 length of the head and body. 1. A. himalayanus, Hodgson. 



Sect. II. Marmots with tails one third or more than one third the length 

 of the head and body. 2. A. hemachalanus, Hodgson. 3. A. caudatus, 

 Jac([emont. 4. A. aureus, Blanford. 



My intention here, however, is not to discuss the conclusions arrived at 

 by Mr. Blanford, but, in giving a more detailed description of /I. dichrous, 

 to enable comparison to be made between it and his A. aureus. 



With regard to the size of the Kabul Marmot {A. dichrous), I had for- 

 merly incidentally mentioned the body as being 17 inches, and tail 6k inches 

 long. These were measurements taken roughly in a straight line. I now, 

 in the subjoined tabular form adapted from Mr. Blauford's jiajier, give 

 more exact data, in inches and decimals, from the specimen in the British 

 Museum, and corresponding to those oiA. aureus given by him (/. c. p. 12;^). 



* Ann. & Mag. Nat. Hist. 1S7.5, (ser. 4) vol. xvi. p. 282. 



t " On the Species of Marmot inhabiting the Himalaya, Tibet, and the adjoin- 

 ing Eegions," by W. T. Blanford, F.R.S., F.Z.S. (Journ. Asiat. Soc.Beng. 1875. 

 pt. 2, no. 3, vol. xliv. pp. 113-127). 



