Boone, Crustacea, Cruise of *'Alva," 1931 39 



tapering distally to an acuminate tip that reaches the base of the ex- 

 posed lower side of the eyestalk and closes the orbital sinus at this 

 point. 



The external maxillipeds are very close-fitting. The exopodite is 

 rodlike, slightly longer than the ischium of the endopodite, with its 

 outer lateral margin moderately convex, the inner one, straight; the 

 apex, triangulate, adjacent to the outer proximal angle of the merus. 

 The ischium is two-thirds as wide as long, with its proximal border 

 obliquely truncate, its lateral margins parallel, the distal margin 

 slightly excavate; the merus is triangulate and is bent upward, ap- 

 pressed to the margin of the epistome and has its proximal margin 

 conforming to that of the ischium and of the exognath, and its inner 

 lateral margin is straight, its outer lateral margin decidedly oblique ; 

 the palp is almost concealed and lies on the inner side of the maxil- 

 liped. 



The eye is set on a short, thick, calcareous stalk, this calcareous 

 margin terminating in two scallops on the dorsal margin of the small 

 cornea, and one scallop ventrally. Only the tip end of the stalk is 

 exposed dorsally but ventrally a wide section of practically the entire 

 length of the stalk is visible, itself occupying the wide orbital sinus 

 which is closed proximally by the antennal joint. The visual range 

 is very limited, the cornea being small, not very convex, lunate in con- 

 tour, the convex margin being dorsal. The visual range is chiefly 

 directed toward the side of the crab. 



Actaeomorpha alvae is distinguished from its nearest congener, A. 

 erosa Miers,* by the fact that it has four large lobes or rounded eleva- 

 tions while A. erosa has five. A. alvae, type is about the same size as 

 the type, A. erosa Miers and is a male also, but the cardiac region is 

 flattish, not elevated. 



Genus: MYRA Leach. 

 Myra fugax (Fabricius). 



Plate 12. 



Type : The first preLinnean record of the species is from Amboina, 



by George E. Rumphius. Fabricius' type came from the "East 



* Actaeomorpha erosa Miers, Journ. Linn. Soc. London, Vol. XIII, p. 184, pi. 

 14, figs. 1-6, 1878. The type of A. erosa Miers was collected at Port Curtis, Aus- 

 tralia, and is deposited in the British Museum of Natural History. 



