§§ BULLETIN 166, UNITED STATES NATIONAL MUSEUM 



segment, which extend far beyond those of the first and have slender, 

 converging tips. Right chela of male swollen, upper and lower 

 margins convex. DactyU of first and second ambulatories as long 

 as the merus, not compressed but with four sides of subequal width, 

 each with a carina. 



Measurements. — Male holotype (19855), total length of carapace 6, 

 width 5.5 mm; ovigerous female (66815), total length of carapace 11, 

 width 11.1 mm. 



Range. — East Florida to Gulf of Mexico; 25 to 118 fathoms. 



Material examined. — See table 26, page 90. 



ETHUSA CILIATIFRONS Faxon 



Figure 20; Plate 24, Figure 2; Plate 25, Figure 2; Plate 28, Figure 4 



Aelhusa ciliatifrons Faxon, Bull. Mus. Comp. Zool., vol. 24, p. 159, 1893 (type 

 locality, Bay of Panama, 153 fathoms; type, U. S. N. M. no. 20630); 

 Mem. Mus. Comp. Zool., vol. 18, p. 34, pi. 5, fig. 3, 3a, 3b, 1895. 



Diagnosis. — Cardiac separated from gastric region by the meeting 

 of the branchial regions on the median hne. Both chelipeds of male 

 slender. Eyestalks very short. Appendages of second abdominal 

 segment slender and no longer than those of first segment. 



Description. — Carapace broader than long, branchial regions much 

 inflated; surface granulated on branchial and cardiac regions, pubes- 



a b 



Figure "iQ.—Ethusa ciliatifrons, male: a, Anterior part from below; 6, abdomen. Slightly enlarged. 



After Faxon. 



cent on gastric region; front and anterior part of lateral border orna- 

 mented with long up-turned cilia. Front between the orbits divided 

 by a triangular median sinus and two slightly shallower lateral sinuses 

 into four triangular teeth of equal length. Orbital sinuses very deep, 

 the external orbital angles reach as far forward as the frontal teeth. 

 Dorsal surface of carapace deeply areolated; the branchio-cardiac 

 lines are deeply impressed and meet in the median hne in front of the 

 heart, cutting off the depressed cardiac area from the gastric. Gastric 

 region uneven with pits and furrows. Eyes small, on very short 

 peduncles, just reaching, w^hen extended, to the posterior angles of 

 the orbital sinuses; the eye is terminal, not wider than the peduncles. 



