NO. 3570 PANDARIDAE — CRESSEY 43 



figured the posteroventral surface of the genital segment (fig. 196). 

 This region shows 2 areas representing legs 5 and 6. I have interpreted 

 the single, broad, spatiilate process as belonging to leg 5 and the curved, 

 clawlike process at the junction of the genital segment and abdomen 

 as leg 6. 



Male. — The male of this species has been described with some 

 figures by Wilson (1907). Because I had no material of the male of 

 this species, I am unable to amplify this description. Wilson did show 

 some modification on the endopod of leg 3 (Wilson, 1907, p. xxv, 

 fig. 103) which supports my contention that this is characteristic of 

 the males of the entire group II of the family. The figures and 

 description are incomplete and more material would certainly be 

 desirable to complete the male description of this species. He stated 

 that the fourth legs are not laminate as in the female but each ramus 

 is 2-jointed and bearing spines and setae. He did not figiu-e this 

 appendage. 



Discussion. — This is a fairly common species occurring on the 

 body surface of a number of pelagic sharks of the genera Isurus, 

 Lamna, and Carcharodon. These 3 genera of sharks compose the 

 family Isuridae (after Bigelow and Schroeder, 1948). The parasite 

 may well be restricted to that group. It is easily separated from 

 members of the genus by the shape of the dorsal thoracic plates. 



Dinemoura discrepans, new species 



Figures 197-217 



Specimens studied. — Eighteen females and 13 males from the body 

 surface of Alopias mdpinus (Bonneterre) from the Indian Ocean 

 (9°24'N, 54°58'E). Holotype female (USNM 113592), allotype 

 male, and 10 paratypes (59 9, 5cfcf) deposited in alcohol in the 

 U.S. National Museum, 10 paratypes (59 9, 5cf cf) in the British 

 Museum (Natural History), and the remaining paratypes in the 

 author's collection. 



Other specimens studied: a single collection from Alopias vulpinis 

 in the Indian Ocean (7°17'N, 55°00'E); a single collection from 

 Alopias superciliosus (Lowe) from Nosy Be, Madagascar; a single 

 collection from Alopias superciliosus from the Pacific Ocean (0°38'N, 

 124°23'W). 



Female. — Body form as in figure 197. Total length 13.9 mm 

 (based on an average of 5 specimens). Greatest width 6.7 mm (meas- 

 ured at widest part of cephalon). Cephalon rounded, 6.7 mm by 

 6.2 mm, slightly wider than long. Thoracic segments 2-4 free. 

 Posterior corners of segment 2 produced to form winglike expansions. 

 Dorsal plates present on segment 4. Plate of segment 4 extending 

 only slightly over anterior portion of genital segment with their 



