NO. 1673. PARASITIC COPEPODS— WILSON. 435 



tip; mandibles of the shape usual in the Pandarinse, the interlocking 

 teeth along- the inner margins being minute and triangular. wSecond 

 maxillae with the basal joint not enlarged as much as in alatus, the 

 terminal spine long, pointed inward toward the mouth-tube, and 

 somewhat enlarged at its base on the outer side. First maxillipeds 

 with a terminal claw fully as long as the joint which bears it, and 

 strongly curved. The accessory claw arises from the posterior border 

 close to the base of the terminal claw, and is about half the size of the 

 latter. Second maxillipeds much swollen, the very broad basal joint 

 with a pair of knobs on its ventral margins, while the knoblike 

 pinchers of the terminal joint cover the whole of that portion of the 

 surface. 



The spines and setas on the swimming legs are arranged as follows : 

 First exopod, 1, 0; 3,111: endopod, 0,0; 0, III: second exopod, 0, I; 

 4, VI: endopod, 0, I; 0, VII: third exopod, 1, 0; 3, V: endopod, 0, 

 I; 0, IV: fourth exopod, 4, IV: endopod, 0, IV. 



Total length, 6.53 mm.; length of carapace on mid-line, 2.5 mm:; 

 width of same, 2.7 mm.; length of free segments, 2.1 mm.; length of 

 genital segment, 1.33 mm. 



Color (preserved material) a uniform l)rownish yellow w^ithout pig- 

 ment spots; the pigment of the paired eyes a deep blue, of the un- 

 paired eye a bright red. 



(curticaudis: curtus, short, and cauda, tail.) 



This species was originally described by Dana, in 1852 and made 

 the type of a new genus called ^' SpeciUigus" from the lenticular 

 bodies or conspicilla situated in front of the eyes. In his genus 

 diagnosis Dana says: "The essential point of difference between this 

 genus and Nngagus is the existence of two large transparent corneas 

 (conspicilla) exactly like those of the Sapphiringe. These conspicilla 

 are attached to the exterior shell, but with some difficulty may be 

 separated. On pressure they proved to be brittle, though rather 

 hard . ' ' 



We now know that similar conspicilla are present in other Nesipjms 

 and Perissopus males, and occasionally in those belonging to some of 

 the other genera. Being common to several genera, therefore, they 

 would have no generic value ; furthermore, they are not found at all 

 in the females of any genus. 



These two facts entirely destroy Dana's distinctions and leave us 

 simply the problem of locating this male among the genera belonging 

 to the Pandarinjp. 



Steenstrup and Liitken in 1861 call attention to the fact that this 

 species was taken in company with Dana's Nogagus validus and Pan- 

 darus hrevicaudis, on the same day and spot, and presmnably from 

 the same fish. They also call the species Nogagus instead of Specil- 

 ligus, but offer no explanation for the change. 



