XXI. NOTES ON THE OCCURRENCE OF 

 APUS IN EASTERN ASIA. 



By Major H. J. Wai^ton, M.D., F.R.C.S., I. M.S., and 

 .Stani^ey Kemp, B.A., Assistant Superintendent, Indian Museum. 



I.— ON THE OCCURRENCE OF .4 P t75 , Latreille , 

 IN THE UNITED PROVINCES OF INDIA. 



By Major H. J. Walton, M.D., F.R.C.S., I. M.S. 



Dr. Annandale informs me that the onl}^ species of Apus 

 known to occur in India is A. himaliyanus, described many years 

 ago by Packard in his 'Monograph of Phyllopod Crustacea. ' Vreden- 

 burg records the occurrence of a species of this or an allied genus 

 in Baluchistan, but has not identified the species {Journ. As. Sac. 

 Bengal, 1905, p. 33). The geographical distribution of the genus 

 Apus appears to be imperfectly known. Geoffrey Smith {Camb. 

 Nat. Hist., Crustacea) only refers to species occurring in Europe, 

 North Africa and Central Australia. As mentioned below, I feel 

 confident that a species occurs in North China. 



It becomes, therefore, a matter of some interest to place on 

 record the fact that an Apus occurs in the plains of India. On 

 March 20th, 1911, the late Major C. J. Robertson Milne, I.M.S.. 

 and I found this Phyllopod to be tolerably numerous near the 

 village of Banel, in the Bulandshahr District of the United Prov- 

 inces. The animals occurred in three or four verj^ small muddv 

 pools formed by leakage from a ' ' distributory ' ' of the Upper 

 Ganges Canal. The pools were in fact scarcel}^ more than 

 puddles, the largest not being more than a couple of yards in dia- 

 meter. Our discovery of Apus was quite a coincidence. About half 

 an hour previously, I had mentioned to Major Milne that I had 

 seen what I believed to have been a species of Apus or Lepidurus 

 at Pekin, about ten years ago; and I remarked that I believed 

 that neither genus occurred in India. When we arrived at the 

 pools we saw some moderately large animals moving about in the 

 mud: on capturing one, I recognized Apus at once. With the 

 aid of some boys we secured about three dozen specimens. 



The erratic distribution of Apus has been commented on by 

 several authors, and was borne out by the present experience. We 

 only found the animals iii a few pools; many adjoining, and appar- 

 ently similar ones containing none. Subsequently for several days 

 I searched unsuccessfully for more specimens in other parts of the 

 Bulandshahr District, both in the Ganges Canal and in many 

 pools in its neighbourhood. Considering the conspicuous size of 



