362 DISCOVERY REPORTS 



postero-lateral spines resembles the terminal spines more closely than in other euphausiids at this 



stage, and as a result the telson looks as though it has eight terminal spines. 



Second calyptopis. Seven specimens examined (Fig. i^a-c). Length range 1-3-1-8 mm.; average 

 length i-6 mm. 



The rostral hood is not as conspicuous as in the preceding stage, although its anterior margin is still 

 serrated. The posterior margin of the carapace is still produced as a sharp spine. 



There is no sign of the median eye and the compound eyes are now quite clearly defined. 



The biramous first antenna is carried on a peduncle of three segments. The outer ramus carries 

 four setae and the inner three. 



The second antenna and remaining thoracic appendages are unchanged. 



The thoracic segmentation is clearly visible. 



There are now five segments and a telson to the abdomen and the rudimentary uropods can be 

 seen within the integument of the telson. The ventro-lateral and postero-lateral spines of the telson 

 are retained, but there are now seven terminal spines. 



Third calyptopis. Five specimens examined (Fig. i^a-c). Length range 2-10-2-33 mm.; average 

 length 2-24 mm. 



The anterior margin of the rostral hood is serrated and the posterior margin of the carapace is 

 produced as a sharp, dorsal spine. The inferior margin of the carapace has developed a small denticle 

 toward its posterior end. 



The globular compound eyes are pigmented and covered by the rostral hood. 



On the outer distal margin of the basal segment of the first antennal peduncle is a strong toothed 

 spine reaching nearly to the end of the third segment. The spines on the two rami of the first antennae 

 are unchanged. 



There is no alteration in the second antennae or the remaining thoracic appendages. 



The abdomen has six segments and a telson. The six segments are naked but the lateral uropods of 

 the telson have developed and are spinose. The outer ramus of the uropod has its outer margin 

 produced as a small tooth. It carries six spines. The inner ramus carries four. There are three pairs 

 of postero-lateral spines and seven terminal spines on the telson. The central terminal spine is much 

 reduced and the remaining three pairs are turned toward it. 



Furcilia stages. Six furcilia stages of E. lucens were found and they are as follows : 



n. = non-setose, s. = setose ; stages 5 and 6 have the second antennal endopod segmented. 



Specimens found: stage 1 = 6, stage 2=3, stage 3 = 5, stage 4=2, stage 5=6, stage 6=8. 



While this paper was being prepared it was necessary to move the collection on which it is based 

 from Bermuda to California. This was done by Military Air Transport and despite the most careful 

 packing and rigorous precautions, the tubes containing the furcilia stages of E. lucens were broken and 

 most of the contents were lost. Only four of the thirty specimens were salvaged and these belong to 

 the first two stages. For these reasons, descriptions and illustrations of the first two stages only are 



