11. NOTES ON DECAPODA IN THE INDIAN 



MUSEUM. 



II. — Descriptions of two new Crangonidae with Observa- 

 tions ON THE Mutuae Affinities of the Genera 

 Pontophilus and Philocheras. 



By Staneey Kemp, B.A., Assistant Superintendent, Indian 



Musemn. 



(Plate ii.) 



In the present paper two new species of Crangonidae, one 

 from New Zealand and the other from the Andaman Islands, are 

 described from material in the Indian Museum. 



An examination of these species and of others which occur 

 on the coasts of Australia and New Zealand has induced me to 

 reconsider the generic status of Pontophilus and Philocheras, with 

 the result that the distinctions between the two genera are found 

 to be so trivial that the only possible course is to revert to the 

 view expressed by Ortmann in 1895/ and to classify all the various 

 forms under Pontophilus, though it will not be necessary to follow 

 him in placing Aegean in the same category. 



So far as I am aware, the sole distinction which can be relied 

 upon for the separation of the two genera rests in the presence or 

 absence of the appendix interna on the endopod of the last four 

 pairs of pleopods, and this, in the two species found on the New 

 Zealand coasts (P. australis, Thomson, and P. chiltoni, sp. nov.), 

 is greatly reduced in size, rudimentary on the fourth pair and 

 entirely missing from the fifth. Consequently, in the case of 

 Crangonidae, the importance of this character seems small in any 

 natural scheme of classification, though in other families of 

 Decapoda, such as the Callianassidae, it affords indications of great 

 systematic value. 



PONTOPHILUS, Leach. 



Pontophilus chiltoni,'^ sp. nov. 



(Plate ii, figs. 6 — 10.) 



Among a small sample oi Pontophilus labelled ''New Zealand," 

 and received here many years ago from the Canterbury Museum, 

 two ovigerous females occur, which evidently represent a species 



1 Ortmann, Proc. Ac. Nat. Set. Philadelphia, xlvii, 1895, p. 182. 



^ I take pleasure in associating with this species the name of Dr. Chas. Chil- 

 ton, whose valuable work on the Crustacea of New Zealand is known to every 

 carcinologist. 



