40 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



teeth on tip and projecting within mouth tube as in other members of 

 group. First maxilla of 2 segments with a palplike process bearing 3 

 short setae on first segment. Second maxilla with usual fringe claw 

 at tip, a stout subterminal spine and a subterminal patch of long 

 hairs. Maxilliped with a short claw at tip. 



Legs 1-4 biramose. Rami of leg 1 2-segmented. Rami of legs 

 2 and 3 3-segmented. Rami of leg 4 1 -segmented and modified to 

 form broad lamellae. Spine and setal formula as follows: 



Leg 5 consisting of a small process bearing 2 short spines, outer 

 plumose the inner naked. Leg 5 located near junction of abdomen 

 and genital segment. 



Egg strings long and straight. 



Color in life cream, generally devoid of pigment. 



Male. — The male of this species was first described by Wilson 

 (1923). Because I had no material of the male of this genus, I am 

 unable to expand Wilson's work. He failed to mention any modi- 

 fication of the endopod of leg 3. Based on evidence in other members 

 of the genus, this modification should be present. On the basis 

 of Wilson's work the male appendages appear to be very similar to 

 those of the female, except that the fourth leg of the male is not 

 modified into broad lamellae as in the female but rather each ramus 

 is 2-segmented and bears spines and setae. 



Remarks. — This copepod has a very long and confusing history. 

 It has been described or recorded under 11 different names. Many 

 of the synonyms have been noted in the literatiue previously (mainly 

 Wilson, 1907) but I have, in addition to these, placed D. qffinis, 

 Thomsen, 1949, in synonymy with D. producta. Shiino (1957) de- 

 scribed and illustrated D. affinis from Japan. These descriptions 

 agree with material I have collected and identified as D. producta 

 from the Atlantic from 4 different hosts, including the same host 

 from which Thomsen described D. affinis. In view of this, I feel 

 certain that only one species of copepod is involved here. 



D. producta is found on several species of pelagic sharks but is 

 most commonly associated with sharks of the genera Lamna and 

 hums. It is probably worldwide in distribution. 



