1888.] G. M. Giles — Notes on the Amphipoda of Indian Waters. 225 



\j dentated. Behind these two teeth comes a plate immovably connected 

 with that bearing them, but placed more to the dorsal aspect of the 

 organ, and bearing six processes or stout hairs of peculiar form. Arising 

 from stout bases they at first become constricted and then expand into 

 a lanceolate terminal plate the borders of which are minutely dentated. 

 It is difficult to determine what may be the function of these peculiar 

 organs, unless it be to finely comminute the mud from which the 

 animal separates the nutritive particles on which it subsists. The 

 first maxillse present no points of particular interest, consisting of the 

 usual pair of hirsutely edged plates. The second maxillaB are some- 

 what peculiar, their inner border being armed with a series of pecu- 

 liarly formed flattened hairs shaped like small lanceolate leaflets. The 

 maxillipeds are four- jointed, pediform, and clawed, and are provided 

 with a pair of elongated flattened inner plates, both these and the main 

 portion of the organ being extremely hirsute. 



The second and third thoracic appendages are but little modified 

 from the plain ambulatory type, presenting only a tendency to the 

 subchelate plan of construction, the dactylus being long and smooth, 

 and the propodite being but little dilated ; the only specialization for 

 grasping being the provision of a series of stout dentate hairs on its 

 posterior border, not unlike those on the mandibles. Both these pairs 

 of appendages are essentially alike, but the third is considerably the 

 longer and is even less specialized than the second, the propodite being 

 barely dilated, and the dactylus, of very moderate strength. The fourth 

 and fifth appendages are quite of the usual ambulatory type, and 

 alike in general plan, but, while the first is the slightest and shortest 

 of all the appendages except the second, the fourth is the longest 

 and stoutest, slightly exceeding the thorax in length. The sixth and 

 seventh are of moderate length, the sixth having its distal articula- 

 tions exceptionally stout, while those of the seventh are exceptionally 

 slight, both have their basipodites strengthened by anterior and pos- 

 terior buttress-like plates ; the eighth has the basipodite very stout and 

 is strengthened behind only by an extremely broad plate, its breadth 

 being one and a half times its length. The eighth appendage is short 

 and its remaining articulations are in general form like those of the 

 seventh. 



The first three abdominal appendages are of the usual swimming 

 type, but are more freely furnished with hairs than is usually the case. 

 They diminish regularly in size from before backwards. The last three 

 are biramous and styloid, armed only with a few short spines on their 

 protopodites. The rami are somewhat flattened and have a bold hollow 

 curve on their inner borders beset with minute dentations (Fig. 10.). 



