Marine Copepoda 43 K 



D. MONSTRILLIDAE. 



33. Thaumaleus bernardensis, n. sp. 



Two males were taken at Station 422, December 12, 1915 (see under Pseu- 

 docalanus). Length of one male 1-9 mm., of the other 2-4 mm. The description 

 relates to the larger. 



The head and first thoracic segment are fused together to form a cephalo- 

 thoracic segment which only slightly exceeds the next three segments (Th 2-4). 

 The lengths of the antennae, of the cephalothorax, and of the three free pedigerous 

 thoracic segments combined, are subequal, the proportions in the order named 

 being: 55 : 56 ; 53. The hind-body, comprising the apodous fifth segment 

 (Th. 5), the genital segment, two following segments and the furca, has the 

 relative length represented by the number 35. Thus the forebody is approxi- 

 mately three times the length of the hind-body. The anal or last abdominal 

 segment shows superficial indication of an imperfect division into two segments, 

 the same appearance being presented by both individuals. Counting it as one 

 segment, the caudal furca is a little shorter, in the ratio of 7 to nearly 8. There 

 is a very small papilla on the ventral side of Th. 5, representing a rudiment of 

 the fifth legs (Fig. 68). 



The ventral lobes of the genital segment have the proportions shown in the 

 figure. Each caudal ramus carries four setae, the most ventral one being much 

 shorter than the others (Fig. 68). 



Fig. 68. Thaumaleus bernardensis. 

 Hind-body of male. 



The distance between the frontal margin and the mouth cone is less than 

 one-third of the distance of the latter from the hinder margin of the cephalo- 

 thoracic segment. On the ventral side of the head there are several chitinous 

 structures intervening between the anterior antennae and the rudimentary 

 mouth-cone. In front of the latter the cuticle is wrinkled, as mentioned by 

 Giesbrecht for Th. longispinosus, and the wrinkles terminate in a small papilla, 



