COPEPOD GENUS RIDGEWAYIA — ^WILSON 143 



clearly separated; ventral margin of last segment deeply incised and 

 showing in lateral view a hooklike process. Rostrum broad and pointed. 

 Urosome 4-segmented; genital segment with distal hooldike process 

 on right side. Caudal ramus twice as long as broad, with four long 

 apical setae (details unknown). Antennule reaching to near end of 

 metasome, 25-segmented. Antenna, exopod 8-segmented. Maxilla 

 with seven v/ell-developed setiferous lobes, of which three belong to 

 basal division. 



Leg 1 (from figure): Exopod 2, outer distal part with inner, narrow, 

 serrate process about half length of outer spine. Inner apical spine of 

 exopod 3 nearly as long as total exopod (about 17:20). For armature 

 of legs 1-4, see under "Discussion" (p. 168). 



Leg 5: Exopod 3 with all four spines shorter than segment, the 

 innermost apical spine of about same length as outer apical spine. 

 Endopod 2, first inner seta placed above middle of segment, at point 

 about 23 percent of total length of segment; first outer seta at point 

 about 54 percent of length of segment. 



Male: Unknown. 



Distribution: Ceylon, from the Muttuvaratu pearl oyster wash- 

 ings. 



Ridgewayia sp. (Madras) 



Suezia sp., Krishnaswamy, 1953, p. 127, figs. 7-9. 



This reference is to a brief description of a single, damaged male 

 specimen found in plankton collected on the Madras coast of India. 

 The record is particularly interesting because it is from the same 

 geographic region as R. typica, and raises the question of whether it 

 may represent the unknown male of that species. Unfortunately, 

 the description given is too incomplete to allow for any decision other 

 than the relationship traceable through the species in which both 

 sexes are laiown. 



The textual description is brief and so may be repeated here exactly 

 as given (with correction of obvious printing errors). "Size: Male 

 0.679 mm. Colour: Formalin fixed specimens appear yellow. Salient 

 features: General body shape cyclopiform. The last thoracic segment 

 with a small projection. The basal 2 of the endopod of first leg with 

 a curved spine. Antennule not prehensile. Fifth leg highly modified 

 and bh-amous." 



Under "Remarks" there is a short comparison with Gurney's 

 figures of the fifth leg of Suezia canalis: ". . . the left leg resembles 

 Gurney's figures exactly while the right exopod differs from it in the 

 second joint being shorter." 



One of the figures given is of the last thoracic segment, and shows 

 a spinous point somewhat similar to that of typica, but smaller. The 



