88 mr. j. a. liddell on a parasitic copepod 



Segmentation. 



The adult Nltocrameira is minute, the total length being 1'26 mm.. 

 •37 mm. o£ this length represents the caudal setee. The body is slender and 

 almost cylindrical, though somewhat compressed in the head region. There 

 is no sharp demarcation between the thoracic and abdominal regions, and the 

 segments are not sharply defined at the margins. 



The third, fourth, and fifth thoracic segments are distinctly ringed, though 

 fused to the head, and the limits of the second can be seen laterally. The 

 first is thoroughly fused to the head, no marking being apparent between 

 them. 



The articulation bet-ween the fore and hind parts of the body, which occurs 

 between the 5th and Gth thoracic segments, allows very free movement^ and 

 in many of the spirit specimens the abdomen is flexed dorsally so as to form 

 almost a right angle with the cephalothorax. 



There are four free abdominal segments excluding the telson, the first of 

 which bears the genital aperture. 



In the female the first and second are thoroughly fused, and no articulation 

 nor any mark is apparent between them. 



In the male the genital segment bears a pair of minute, indistinctly bilobed,. 

 setose projections, which may perhaps be regarded as the vestiges of a ]iair of 

 appendages. 



The eo-gs are carried in an eog-sac reoularlv arranoed in a double row, 

 and number from seven to twelve. 



The spermatophore is pyriform, and hooked at the " neck'' end. 



The rostrum is small, narrow and conical. The caudal rami are short, and 

 bear only a few setee. The large seta is roughly one-third of the total length 

 of the body. Another seta less than half this length lies externally to it, and 

 there are three small setse in addition. 



The only structural trace Nltocrameira shows of its semi-parasitic 

 existence is the extreme smoothness of the urosome. 



The strong claw-like posterior ramus of the 2nd antenna of the Nauplius 

 larva may also be a modification for attachment to the w'alls of the egg-sac. 



ApPENDAC4ES. 



1st Antenna. — The first antenna is eight-jointed, the third joint being in- 

 both sexes small, and bearing the greatest number of setse. 



In the female there is a distinct bend at the third joint. The fourth bears 

 a long three-jointed sesthetasc. The last two joints are small, but quite well 

 defined. 



In the male the fourth and fifth joints are fused and expanded. The 

 . sesthetasc, which is blunter terminally than in the female, rises from the 

 point of fusion of the two segments. 



