3. Euphausia gibboides, Ortm. 



Euphausia gibboides Ortmann, op. cit. p. 12, Pl. 1. fig. 5. 

 Locality. — Stat. 1768, 1 spécimen. 



Genus THYSANOPODA, H. Milne-Edw. 



This genus is chiefly distinguished by having the penulti- 

 mate pair of thoracic legs rather well developed, shaped as the 

 preceding pairs, while the last pair has the endopod obsolète 

 but the exopod well developed. Eight species have been 

 described, and fîve are added in the présent paper. Especially 

 two of thèse new forms, T. insignis and T. egregia, differ very 

 materially fromat least most of the other species in the structure 

 of the maxillulœ, while their abdominal luminous organs seem 

 to be at least rather small, the posterior pair of thoracic organs 

 small or perhaps wanting in one of them, and the anterior 

 thoracic pair not traceable. Nevertheless, I will at présent not 

 establish a new genus for the réception of thèse two forms, 

 because the maxillulœ (and the luminous organs) have not been 

 examined in several of the species described in the literature, and 

 having seen no spécimens of some of thèse species, I am unable 

 to say anything on their organs mentioned. Especially T. cristata 

 G. O. Sars seems to differ considerably in some features from 

 forms as T. tricuspidata M.-Edw. and especially T. obtusifrons 

 G. O. Sars and allied species, but Sars says nothing on the 

 maxillulse and the luminous organs in T. cristata. 



It may be useful to give an analytical conspectus of the 

 species hitherto known from the Atlantic Océan. 



A. Carapace with a pair of latéral marginal denticles near the 

 posterior end. 



a. Carapace with a dorsal spine behind the base of rostrum 

 and besides a pair of latéral marginal denticles at the 

 base of the maxillipeds 1. T. tricuspidata M.-Edw. 



