— i6 - 



Remarks. — This species is common in the Atlantic. In 

 gênerai aspect it is similar to T. distinguenda, but the latter 

 species differs in some particulars, especially in having no 

 latéral marginal denticles on the carapace. T. oblusifrons Sars 

 lias been established on spécimens from the Pacific and has not 

 yet been found in the Atlantic; the Plankton spécimens refer- 

 red by Ortmann to T. obtusifrons certainly belong to T. vulga- 

 r/s, because Ortmann expressly states that they have minute 

 latéral marginal denticles on the carapace. 



Thysanopoda pectinata, Ortm 



(Fig. 12) 



Thysanopoda pectinata Ortmann, op. cit. p. 10, Pl. I. fig. 4. 

 Locality. — Stat. 1639, 2 spécimens (one large, the other 

 less than half-grown). 



Remarks. — Adult spécimens measure about 35 to 44™ in 

 length. To Ortmann's description some notes must be added. 

 The front part of the upper side of carapace is rather similar to 

 that in T. vulgaris, but the keel is higher at the dorsal organ, 

 the shallow sublinear impressions are somewhat shorter, the 

 front end is not so obtuse as in T. vul- 

 garis, each half of its margin being slight- 

 ly convex, while the tip terminâtes in a 

 minute tooth directed obliquely upwards 

 and forwards. Eyes rather small, brown. 

 The basai joint of the antennular peduncle 

 is at the upper inner side produced into a 

 lobe which, seen from the side (fig. 1 2), ter- 

 minâtes in a small short triangular acute 

 process which is shorter than deep, when 

 the insertion of the most distal one of the 

 coupling setœ is considered the base of the process. The 

 lower oblique margin of this lobe on the inner side of the 

 antennula is furnished with a number of stiff short setae 

 projecting downwards and forwards, and each of them termi- 

 nâtes in a hook; thèse setae on the left antennula are cou- 

 pied together with those of the right antennula, with the resuit 



Fig. 12. — First and se- 

 cond joints of the pe- 

 duncle of left anten- 

 nula of T. pectinata, 

 seen from the outer 

 side. 



