[fraser] COPEPODS PARASITIC ON FISH 61 



Chondracanthus gracilis new species 



PI. VI, Figs. 84-93 



Female. — Body long and slender. Céphalothorax slightly broader 

 than long, rounded posteriorly and anteriorly, a distinct joint separa- 

 ting it from the rest of the body. The second thoracic segment is 

 free. The remainder of the body is elongated — oval in shape. A 

 pair of lateral processes stand out distinctly from the body about 

 half way back. The posterior processes are long and slender, grad- 

 ually tapering and slightly curved, their length more than three- 

 fourths the greatest width of the body. There are two dorsal pro- 

 cesses along the median line, the anterior one being about one-third 

 of the way back and the posterior not much anterior to the end of the 

 segment; the former is not very strongly developed and in some 

 specimens is scarcely noticeable; the latter is much more distinct, 

 being nearly the same size as one of the lateral processes. The 

 genital segment is small, about one-fourth the width of the body. 

 The abdomen is nearly as wide but is constricted anteriorly and 

 posteriorly. The egg strings are long and slender, not far from being 

 as long as the whole body. The eggs are small and very numerous. 



The first antennae show indication of division into three joints; 

 there is one seta on the intermediate joint and four on the terminal. 

 The second antennae are not particularly stout and they do not taper 

 to so sharp a point as usual. The mandible is stout, strongly curved, 

 with the teeth on both sides stout. The terminal joint of the maxilla 

 is turned strongly forward, is slightly curved and has eight or nine 

 small but sharp teeth on the convex surface. There is no accessory 

 spine present. The terminal spine of the maxilliped is set well back 

 from the end of the joint that supports it and is not in the same straight 

 line with it. The end of the joint is roughened by very rough spines. 

 The first pair of legs is attached to the free thoracic segment. The 

 second pair is similar and is attached just behind the joint that sepa- 

 rates the second segment from the remainder of the body. 



Total length to end of posterior processes 8-2 mm., length of 

 céphalothorax 1-2, width 1-4, width of body 2-1, width of genital 

 segment 0-5, length of egg strings 7 • 4. 



Male: Body short and deep. Céphalothorax fîve-eighths of the 

 total length ; breadth three-fourths of length ; depth nearly as great as 

 width. Little or no indication of segmentation between head and 

 thorax. The second thoracic segment is free, much narrower than the 

 céphalothorax. The third segment is smaller than the second and 

 the fourth smaller than the third. The genital segment is longer than 



