1888.] G. M. Gi\es— Notes on the Ampbipoda of Indian Waters. 239 



and quite distinct from each other, the first four forming conical 

 processes directed obliquely forwards and downwards from their cor- 

 responding pleura, and the hinder three being longer, but very narrow, 

 plates. 



The first three ahdominal segvients are subequal, nearly cylindrical, 

 and are a little shorter than the first thoracic segment ; the last three 

 are very diminutive, and the telson short, squamous, and semilunar. 



The antennule is stout, less than half as long as the body. Its pe- 

 duncle forms three-fourths of the length of the organ, and consists of 

 three joints, subequal in length, but diminishing progressively in stout- 

 ness, and the flagellum consists of five stout longish articuli. Both 

 peduncle and flagellum are armed with a large number of long stiff hairs, 

 and the flagellum is, in addition, provided below with a series of flexible 

 flattened hairs quite different from the others. The antenna is pedi- 

 form and much the largest of all the appendages, being very stout and 

 nearly as long as the entire thorax. Almost the entire length of the 

 organ is formed by the peduncle, the flagellum being represented by a 

 single short, stout joint terminated by a pair of strong claws. The 

 first and last pedunculary articuli are subequal and rather short, the 

 second a little longer than these, and the third and fourth subequal 

 and very long, forming together two-thirds of the length of the organ, 

 which is profusely armed with long, stiff hairs. 



The gnathites, as far as they could be examined, present no points 

 of peculiar interest, the mandibles being of simple form and palpate, 

 and the maxillipeds small and unguiculate. 



The first of the gnathojpods is but feebly subchelate, no palm being 

 developed to the propodite ; such grasping power as it may have being 

 furnished by a number of fine serrations on the dactylopodite and some 

 stiffish hairs on the protopodite. The appendage is as long as the pedun- 

 cle of the superior antennsB ; the second gnatbopod, though but little 

 longer, is much stouter and has the protopodite much dilated, the palm, 

 though rather oblique, being strongly armed with three formidable 

 teeth, and the dactylopodite being strongly serrated. The dactylopodite 

 also presents the following additional peculiarities : first, it is armed 

 in its anterior border with one or two hairs, a most exceptional circum- 

 stance, and, secondly, it is really trifid when seen from above, as, from a 

 point about half way along its length, a powerful secondary tooth pro- 

 jects obliquely on either side; these latter being but little exceeded 

 by the main central tooth either in length or stoutness. As in the 1st 

 gnatbopod, the carpo-propodital articulation is rather oblique. 



The next two thoracic appendages (4th and 5th) are short, being 

 only as long as the two first joints of the peduncles of the anten- 



