30 



OSCAR SUND 



(REP. OF THE "MICHAEL SARS" NORTH 



Benthesicymus Hjorti n. 

 (PI. II, fig. 4). 



sp. 



This species bears a close resemblance to B. crenatus 

 Bate sharing with it the outstanding feature of having 

 the posterior edge of the fourth pleosomite saw-toothed 

 (see fig. 48). Our species which might be considered the 

 Atlantic representative of the Pacific species B. crenatus, 

 differs from it in carrying only two teeth on the upper 

 edge of the rostrum (the tip not included) and no spine 

 on the carapace behind the rostrum. 



Fig. 48. Benthesicymus Hjorti. Detail of abdomen ( 5 /i). 



The eyes are devoid of pigment. The cornea is 

 scarcely broader than the stalks which do not reach as 

 far as the tip of the rostrum, neither to the extremity of 

 the first joint of the antennular peduncles. This joint is of 

 about the same length as the two outer joints together. 

 The stylocerite ends in a short triangular tooth. 



The carapace is very smooth, the sulci being nearly 

 obliterated. Of spines only the branchiostegal is seen; 

 it is very small. 



The tail-fan is large. Telson is long, nearly three 

 fourths as long as the outer uropod. 



In all three specimens were taken, two males at st. 53 

 (trawl, 2615 — 2865 m.j and one female at st. 35 (trawl 

 2603 m.). Below is given some measurements, in mm., 

 of these specimens. 



Length of carapace 



Do, rostrum included.... 



Length of scaphocerite, to tip of tooth 



- outer uropod, do. 



do., total 



„ - inner uropod 



- telson 



st. 53 



35 

 42 

 21 

 20 

 24 

 17 

 16.5 



st. 53 



26 



30 

 16 

 15 

 18 

 13 

 13 



? 

 st. 35 



44 



55 



24.5 



23 



28 



20 



20.5 



Benthesicymus longipes Bouvier. 

 Benthesicymus longipes, Bouvier 1908. 



This species has formerly been taken only once, near 

 the Cap Verde Islands, in a depth 3890 metres. 



Two of the specimens obtained by the "Michael 

 Sars" were taken at a depth not exceeding 3000 metres 

 (length of wire paid out 4000 metres) bottom being 

 found in a depth of 3886 metres. The capture must 

 therefore have occurred at a distance of not less than 

 800 metres ftom the bottom, thus establishing B. long- 

 ipes as a plankton- animal. 



"Michael Sars" 1910, st. 51, large net, 4000 metres 

 wire out. Two males, length of carapace (C) 22 and 

 20 mm. respectively. St. 35, trawl, depth 2603 metres, 

 one defect specimen (C = 19). 



Benthesicymus ? carinatus Smith. 

 Benthesicymus? carinatus, Smith 1884. 



Only one, very mutilated specimen of B. carinatus 

 was obtained, a female with a carapace length of about 

 30 mm., at st. 82, at a depth of about 2000 metres (large 

 tow-net, 3000 metres wire out). Drawings of the very 

 characteristic mouth parts are given in fig. 49. The form 

 of these, especially of the 2. mxp., suggests for this species 

 an intermediate position between the genera Amalopenceus 

 and Benthesicymus. 



P/esiopenaeus Edwardsianus I. Y. Johnson. 

 Penceus Edwardsianus, I. Y. Johnson, 1867, p. 897. 

 Plesiopen&us Edwardsianus, E. L. Bouvier, 1908, p. 64, ubi. syn. 



Of this magnificent species good catches were made 

 with the trawl at the following stations: 

 at st. 23, depth 1215 metres, 54 males and 83 females, 



and one young, 

 at st. 24, depth 1615 metres, one male and one female, 

 at st. 41, depth 1365 metres, 18 males and 7 females. 



The length of carapace was measured in all the 

 specimens except four defect ones. The females are 

 generally much larger as will be seen from the measure- 

 ments. In addition to those contained in the table four 



