No. 2104. NORTH AMERICAN PARASITIC C0PEP0D8—WILH0N. 121 



terminal and slightly curved, the other on the inner margin near the 

 base. These appendages are also furnished ^Yith very powerful 

 muscles and are probably used in burrowing. The maxillipeds are 

 reduced to mere spines, with which are still connected two or three 

 weak muscles whose only service seems to be to show that the spines 

 are really rudiments of mouth parts. In the posterior end of the 

 genital segment, just inside the vulva, can be seen the enlargement of 

 the oviduct on either side which serves as a receptaculum seminis. 

 The entire abdomen is monilliform and terminates in two large anal 

 laminae, each well supplied with setae. 



In an older specimen, 35 mm. long, the rudiments of the mixil- 

 lipeds have disappeared, but the other appendages remain intact; 

 the genital segment is ridged transversely, and the plumose appen- 

 dages of the abdomen have started as broad bluntly rounded proc- 

 esses, one on either side of each monilliform division of the abdomen. 



Color. — Head and neck, or buried portions of the body, pale yel- 

 low, often with a reddish tinge from the contained blood; genital 

 segment and abdomen dark cinnamon brown, banded transversely 

 with yellow ; egg strings dark orange yellow. 



Total length, 150-200 mm. Head, 8 mm. long, 10 mm. wide. Neck, 

 50-GO mm. long, 3 mm. wide. Genital segment, 70-80 mm. long, G mm. 

 wide. Abdomen 40-50 mm. long. Egg strings 200-350 mm. long. 



(filosus, thread-like.) 



/Remarks. — The history of this species is rather complicated. Lin- 

 naeus described his Pennatvla flosa as follows: "P. stirpe rachi 

 utrinque pennata: basi tentaculis duobus. Bocc. mus., 1G74, p. 286, 

 t. 28G. Habitat in M. Mediterranei Xiphiis. Setae 2, rubrae. ad 

 basin rachios pennatae insertae, ipsaque rachi longiores." ^ 



Stebbing pertinently remarked ^ that the only thing of any specific 

 value in this description was the name of the host. But, fortunately, 

 subsequent investigators have added useful characters that do possess 

 specific value. 



Guerin-Meneville published^ a figure of Pennatida flosa that 

 .shows enough details to identify the species. Cuvier said,* "There 

 is one species (Pennella fllosa) in the Mediterranean, 7 or 8 inches 

 long, which penetrates the flesh of the swordfish, the tunny, and the 

 sunfish, and torments them horribly." Milne Edwards adtlecl,^ " Body 

 very long, slender, and straight; head swollen, carrying behind two 

 short and obtuse horns. Appendages of the abdomen penniform, 

 slender, and joined two by two at their base." 



> .'Cystoma Naturae, ed. 10, 1758, p. 819. 



* South African Crustacea, 1005, pt. 3, p. 188. 

 « Ucgne Animal, IS.'i", vol. 2, pi. 9, fig. 3. 



* I.lein, 1S30, vol. .3, p. 257. 



* IJistoire Naturelle des Crustaccs, vol. 3, p. 523. 



