NO. 1404. PARASITIC COPEFODS—CALIGID.^— WILSON. 611 



From this table it can be seen that the species carangis is about 

 twice the length of the other two, which are themselv^es approximately 

 equal. But the carapace in carangis is only one-seventh the entire 

 length, while in inegacephalux it is a (piarter. The free segment in 

 megacepJialus is actually three and a half times as long as in carangis^ 

 or proportionately seven times the length, and yet it is only half as 

 long as the free segment in laciniatus. The relative width of the 

 genital segment and carapace also vary greatly in the three species. 



And if Kroyer's figure of the ventral surface of ladnuitux is to be 

 trusted for details of the appendages, the second maxillipeds in that 

 species have no tooth at the base of the terminal claw, and there are 

 no accessory spines in connection with the furca. 



Genus ECHETUS Kroyer. 



Carapace minute, a very small portion of the entire length; frontal 

 plates well defined and furnished with lunules. First maxillfe and 

 furca lacking; second maxilla simple. 



Free thoracic segment ver}" narrow and much elongated, forming a 

 long neck connecting the carapace and the genital segment. 



First and fourth legs uniramous, the fourth pair partiall}" rudi- 

 mentary; second and third pairs biramous. Genital segment swollen 

 several times the size of the carapace, without appendages or proc- 

 esses. Abdomen an elongate spindle attached to the genital segment 

 by a very short and narrow neck; anal lamina^ linear, minute. Egg 

 cases a little longer than the abdomen, eggs as in Caligus. 



{Echetus^ the name of a king mentioned in Odyssey, line 85.) 



" Eii'^Exeruv lia6iXi}a, fiftOTcljv SifXij^iova TtdiTcov." 



This name is peculiarly appropriate, as can be seen from a translation 

 of the context, ''And 1 shall send you to King Echetus, destroyer of 

 all men, wdio will cut off your nose and ears with pitiless steel, and 

 draw out your vitals and give them to dogs to eat raw." 



Only one species known. 



ECHETUS TYPICUS Kroyer. 



Plate XVII. 



Female. — Carapace about one-twentieth the entire length, longer than 

 wide. Frontal plates well defined and furnished with small lunules, 

 which are widelj" separated and not fully visible dorsally. The median 

 incision l)etween the two plates is as deep as the plates themselves, 

 reaching the margin of the cephalic area. In this incision can be 

 plainh' seen the remains of the base of an attachment filament similar 

 to those in Caligus. 



