NO. 2286. THE NEW COPEPOD FAMILY SPHYRIIDAE— WILSON. 565 



External family characters of inale. — Body folded upon itself and 

 unsegmented in Sphyrhn^ straight or curved and more or less seg- 

 mented in the other genera ; made up of two regions, a cephalothorax, 

 bearing the antennae and mouth parts, and a thorax destitute of ap- 

 pendages. Two pairs of antennae, second pair chelate; proboscis 

 long and retractile like those of the Lernaeopodinae. First maxillae 

 biramose, second pair one-jointed, uncinate; maxillipeds with fused 

 basal joints, terminal joints free, uncinate. 



Internal family characters of male. — Digestive tube extending 

 straight through the body, nearer the ventral surface. Testes paired 

 in the posterior dorsal portion of the cephalothorax, often protruding 

 strongly as spherical swellings; sperm ducts lateral, not convoluted 

 but surrounded by large cement glands ; sphermatophore receptacles 

 in the genital segment. A large frontal gland above the anterior end 

 of the stomach; a large fused maxillipedal gland in the basal joints 

 of the maxillipeds; smaller glands in the first and third thorax seg- 

 ments and near the anus. 



Remarks. — This family is at once distinguished from the Ler- 

 naeidae by the presence of adult pigmy males attached to the females, 

 while in the Lernaeidae the males do not pass beyond the fourth 

 copepodid stage and are never found with the adult females. The 

 Sphyriidae also differ in the position and arrangement of the repro- 

 ductive organs and in the presence of dorsoventral muscles, separat- 

 ing the convolutions of the oviducts and forming by their contrac- 

 tion pits or grooves on the dorsal and ventral surfaces of the trunk. 

 Still another difference is found in the complicated system of pro- 

 cesses attached to the itestine in the trunk of Sphyrion and Rehelula^ 

 which has no counterpart in the Lernaeidae. 



In the elongation of the body of the female previous to and during 

 burrowing all the thoracic segments take a part, the third and fourth 

 segments being elongated the most. The trunk is composed of a part 

 of the fourth and all of the fifth and sixth scgiiicnts while in the 

 Lernaeidae this is true only of the genus Lernaea (Leriiaeocera). 

 And in that genus the arrangement and position of the reproductive 

 organs is like that of the other Lernaeans and radically different 

 from the present family. 



The males of the Sphyriidae closely resemble those of the Lernaeop- 

 odidae, particularly the genera Achthci^es., Salmincola, Lernaeopoda, 

 and Clavellisa. but the females bear no resemblance whatever, lacking 

 the peculiar second maxillae, having lateral processes or horns on the 

 cephalothorax, and burying the head and neck in the tissues of the 

 host. 



From the Chondracanthidae, with which family some of the present 

 genera have at times been placed, the females differ in the absence of 

 prehensile second antennae and thoracic legs and in the presence of 



