141 



The 2nd joint of the antennular peduncle is much the longest : the inner 

 antennular flagellum is extremely slender, the distal end of the thickened basal 

 portion of the outer flagellum is fringed with long silky setae. 



The larger cheliped in the male is longer than the entire body and for an 

 Alpheus is slender; not quite three-fifths of its length is contributed by the 

 hand. The arm, which has a spine near the far end of the upper border and a 

 series of distant finely-acicular movable spinelets along the inner border, is about 

 two-thirds of the length, and more than half the thickness, of the palm. The 

 palm, which is slender subcylindrical and gently tapering, is as long as the 

 combined carapace and 1st abdominal somite. The dactylus, which is decidedly 

 shorter than the fixed finger, is only about one-third the length of the palm, and 

 is furnished with a small tubercle that fits into a round hole in the opposable 

 edge of the fixed finger. 



In the smaller cheliped the palm is hardly half the length of the carapace 

 and is equal in length to the fingers, which are long slender and hooked at tip. 



The slender 2nd pair of legs reach, by their chelae and last 2 segments of 

 the five-jointed carpus, beyond the carpal articulation of the hand. 



Although the number and arrangement of the branchiae is typical, and 

 although the gill-elements are arranged in two series on either side of a stem as 

 in typical phyllobranchiae, yet the gill-elements are narrow thick filaments and 

 not thin broad plates, so that the gills have a lax and feathery appearance. 



Colour in life, transparent blood red. 



In the largest male the carapace is 14 millim. long, and the abdomen 24 

 millim., measured in the middle line, and the larger cheliped 41 millim. An 

 egg-laden female is a good deal smaller. 



From the Bay of Bengal, 193, 145-250, and 270 fathoms, and from the 

 Andaman Sea, 188-220 fathoms. 



-P. -, -v 8857 /m f ,-, s 4243-4244 6283 6759-6760 



Regd. IN os. (Type of the species) : 7 : : - . 

 85. Alpheus Sheartlieif Alcock and Anderson. 



Alpheus Shearmci, Alcock and Anderson, Ann. Mag. Nat. Hist., April 1899, p. 283. 

 ILLUSTRATIONS OF THE ZOOLOGY OF THE INVESTIGATOR, CRUSTACEA, PLATE XLI. FIG. 4. 



Integument very thin but firm, smooth and polished. Rostrum minute, 

 not longer than the equally acute supra-ocular spines, not produced backwards 

 as a carina. 



Abdominal pleura broad fore and aft and broadly rounded ; those of the 

 2nd somite widely overlap those of the 1st and 3rd somites. 



The first joint of the antennular peduncle is the longest ; the antennular 

 flagella are not setose. 



