EUPHAUSIA DISTLXGUEXDA. 2S7 



And after a renewed examination of the "Siboga" material I consider my inter- 

 pretation or reference of these animals as tiuite certain. The above-described 

 larvae must therefore belong to a .species alhed to T. monacantha {T. agassizii) 

 and according to my knowledge of young animals of T. pectinata, T. orientalis, 

 T. aequalis, and T. ohtusifrons they cannot belong to any of these forms, but 

 most probably to T. cristata G. O. S., which is larger than T. monacantha and 

 agrees with it in having a lateral furrow somewhat above the lower margin of 

 the carapace. 



Euphausia distinguenda H. J. Hansen. 



Plate 12, figs. 2a-2c. 



Last Furcilia-Stage. — Slender. — The frontal plate (fig. 2b) is large, scarcely 

 twice as broad as long, anteriorly very broadly rounded but with a cjuite minute 

 acute tooth representing the rostrum. The dorsal keel of the carapace situated 

 nearly equally distant from the rostrum and from the posterior margin; it is 

 high, subtriangular, with the front margin rather steep; the tooth situated far 

 behind on the lateral margins of the carapace is large. 



The eye-stalks are uncommonly long, almost longer than broad (fig. 2b) 

 and conspicuously longer than deep (fig. 2a). — The antennulae are half devel- 

 oped; the distal process from the first peduncular joint reaches not fully to the 

 end of third joint; the flagella are equal in length, somewhat longer than the 

 sum of the two distal peduncular joints, three-jointed. — The antennae have 

 the exopod somewhat shorter than the endopod and not yet developed as 

 squama. — The maxillipeds with botli rami eejual in length and the exopod one- 

 jointed. — First pair of thoracic legs twice as long as the maxiUipeds; endopod 

 with the full number of joints with only a few short setae at the end; the exopod 

 not cjuite half as long as the endoijod; a minute bipartite branchia is visible. 

 Second pair of legs nearly rudimentary, with a minute branchial rudiment; 

 third pair scarcely visible. 



The four anterior pairs of pleopods with both rami setiferous; the cxojkhI 

 as long as the stalk, while the endopod is minute. Fifth pair of jjleopods small, 

 naked, with a transverse suture. — Distal part of telson (fig. 2c) with three 

 terminal spines, the intermediate spine somewhat longer than the others, and 

 with three pairs of lateral spines, the distal pair a little longer than and twice as 

 broad as the intermediate, while the proximal paii- ai'e minute. 



Length of the specimen described and figured 2.8 nun. 



The specimen is from the '"Albatross" Sta. 4588; October 12, 1904. 

 Surface. 



