368 BUL,LETIN OF THE BUREAU OF FISHERIES 



First maxilla ending in a single claw; second maxilla with two claws of the same size; maxillipeds 

 two-jointed, the basal joint unarmed, the terminal joint ending in five curved claws, at the base of which 

 is a large rounded knob, and back of the knob on the inner margin a tiny process terminated by a single 

 spine. The bases of the maxillipeds are so far behind the mouth tube that their tips do not quite reach 

 the bases of the second maxillae. 



Color of young specimens a uniform creamy white, turning more or less dark reddish brown with 

 age, the tips and sometimes the entire branches of the cephalic horns dark brown, almost black. 



Body length (excluding horns and egg strings), 8 mm.; greatest diameter, 0.70 mm.; diameter of 

 posterior enlargement, 1.40 mm. I,ength of egg stjjngs, 2.10 mm.; greatest diameter of same, 0.70 mm. 



{cruciata, torturing or tormenting.) 



Remarks. — The parasite is usually attached nearer the head than the tail of the fish ; the head, horns, 

 and one-third of the body are buried in the flesh, usually beneath a scale or in the angle between two 

 scales, and in such a way that the posterior two-thirds of the body points diagonally backward, and 

 when the fish is in motion hangs close to the body of the latter. This species is associated with the 

 glochidia of Anodonta corpulenta upon the largemouth black bass, and suggests that these external glo- 

 chidia will subsequently be found also upon the other fish which serve as hosts for this Lemaeoceran. 



Lemaeocera tortua KelHcott. (PI. lxxiv, fig. 111-113.) , 



LerncBocera tortua Kellicott, 1S81, Proc. Amer. Soc. Microscopists, vol. 2, p. 41. 1 unnumbered plate. 



Host and record of specimens. — Originally obtained by Kellicott from Grindstone Creek, a tributary 

 of Lake Ontario, in July, 1880. Each I,emEEocera was deeply buried in a tumor caused by its presence 

 just behind, or in the axilla of, a pectoral fin of "Ameiurus catus Gill. " According to Dr. B. W. Ever- 

 manu A. catus does not occur in Lake Ontario, the forms foimd there and usually referred to it being 

 either melas or nebulosus, in this instance more probably the latter. Seven females were taken from 

 A. nebulosus SLtthomaston, Ga., by B. B. White and have been given catalogue no. 12030, U. S. National 

 Museum. A single female was taken from Icialurus furcatus at Falrport, Iowa, June 2, igio, and has 

 received catalogue no. 47772, U. S. National Museum. 



Specific characters of tlie female. — Body straight and somewhat enlarged posteriorly; a lateral horn on 

 either side of the cephalothorax, dichotomously branched, tuberculated, and standing out from the 

 head at right angles to the body axis, so that the two horns are in the same straight line; a single dorsal 

 horn, forked at the apex; all three horns strongly flattened anteroposteriorly and half as wide as long. 

 In the Iowa specimen the horns are flattened, but the branches are much smaller and more slender 

 than those of the Georgia specimens. Body sometimes obsciu-ely segmented, with no lateral tubercles 

 at the posterior end; the median dorsal tubercle or abdomen comparatively long and three-quarters of 

 the diameter of the body; anal papillae large and well armed with plumose setae; egg strings moderately 

 long (one-third the length of the body) and subcylindrical, tapering posteriorly. 



Head ovate, considerably longer than wide; first anteimae four- jointed, the three distal joints about 

 the same length, the proximal joint shorter; second antennae three- jointed , the two distal joints about 

 the same length, the proximal one much shorter; the terminal joint is enlarged and tipped with a long 

 curved claw and several curved setae; second maxillae comparatively stout, each terminating in two 

 large curved claws; maxillipeds rather short and stout, the terminal joint much narrower than the 

 basal and ending in foiu- or five slender claws, with a large knob at their base, but no papilla on the inner 

 margin. 



The two lateral cephalic horns are united across the front of the head and the ridge thus formed 

 projects a long ways ventrally , owing to the anteroposterior flattening of the horns. On the ventral edge 

 of the ridge, or a little removed from it on the posterior surface, is the first pair of swimming legs. 



Color (preserved material), a rich reddish brown. 



Body length (excluding horns and egg strings), 11.25 mm.; greatest diameter, 0.75 mm.; combined 

 length of lateral horns, 3.90 mm. Length of egg strings, 4 mm. 



Remarks. — The foregoing description and the accompanying figures agree fully with those given 

 by Kellicott, except in the position of the fourth swimming legs (see p. in). In all the specimens 

 obtained at Thomaston, Ga., the fourth legs are relatively much nearer the posterior end of the body 

 than is represented by Kellicott, and there is no indication of another groove posterior to them or between 

 them and the third pair. This species does not seem very widely distributed nor very abundant in any 

 locality. Wliile its hosts are common in the Mississippi River, only a single specimen of the parasite 

 has thus far been found. 



