ARGULID^E OF THE WOODS HOLE REGION. 131 



Emerging larva totally unlike that of cdtostomi and foliaceus, in a more advanced cyclops stage, with 

 all the appendages except the first maxillipeds like those of the adult. < larapace elliptical, longer than 

 wide, partly covering the base of the first pair of legs only; posterior sinus very wide and shallow ; 

 eyes one-fifth the width of the carapace, closely approximated, almost touching the anterior margin. 

 Thorax narrowing gradually from in front backward; abdomen broad-elliptical, nearly as wide as long; 

 anal sinus broadly triangular, papillae basal; a very distinct row of small skin glands around the edge 

 of the lateral areas of the carapace; rive or six much larger ones along either margin of the abdomen. 

 Antennas thicker and stouter than in the adult, with the spines relatively larger; anterior maxillipeds 

 four-jointed, terminating in two sickle-shaped hooks, the ventral one armed with barbs; there is also 

 a stout spine on the anterior border of the terminal joint; posterior maxillipeds much smaller, five- 

 jointed, each of the four basal joint," armed on their ventral surface with a long curved spine and man] 

 shorter ones; basal plate with only two posterior teeth, but with a long spine on its outer margin. 

 Swimming legs all perfectly developed; exopods one-jointed, with two long, plumose, towing eetse; 

 endopods of first pair three-jointed, first and second joints with sharp spines on their posterior border, 

 third joint terminating in two similar spines, placed side by side; endopods of three posterior pairs of 

 legs two-jointed with a single rowing seta. 



The following is ;i list <>f the hosts upon which any species of Argulus has been 

 found in the vicinity of Woods Hole: 



Common skate, Raja erinacea Mitchill. 



A. laticauda, .1. megalops. 

 Brook sucker, Catostomus nommersonii i Lacepede). 



A. catostomi. 

 Chul' sucker, Erimyzon sucetta oblongus (Mitchill). 



A. catostomi 

 Common eel, Anguilla chrisypa Rafinesque. 



A. laticauda. 

 Alewife, Pomolobus pseudoharengus ( Wilson). 



.1. alosx. 

 Smelt, Osmerus mordax (Mitchill). 



.1. tllnsiir. 



Killi-fish, Fundulus majatis (Walbaum). 



.1. fundulus, A. megalops. 

 Killi-fish, Fundulus heteroclilus I Linnaeus). 



.1. fundulus, A. megalops. 

 Sculpin, Myoxocephalus a neus I Mitchill ). 



A. 'laticauda, A. megalops. 

 Sea robin, Prionotus carolinus I Linnaeus). 



A. megalops. 

 Blenny, sp. 



.1. laticauda. , 

 Tomcod, Mierogadus tomcod I Walbaum ). 



.1. laticauda, A. megalops. 

 Sand-dab, Hippoglossoides platessoides < Fabricius). 



.1. megalops. 

 Summer flounder, Paralichthys dentatus • Linnaeus). 



A. laticauda, A. megalops, A. alosae. 

 ( lommon flat-fish. Pseudopleuronectes americanus ( Walbaum). 



.1. laticauda, A. megalops. 

 Window pane, Lophopsetta maculata (Mitchill). 



.1. megalops. 

 Goose-fish, Lophius piscatorius ( Linnseus). 



A. megalops. 



