The general form of the body is much like that of Bcdoti, so much so that at first 

 the two species were confused with one another. But it can really be quite readily distinguished 

 by the larger head, the elongated eye-pigment, the little collarette, and the smaller extension of 

 the posterior fin. The dotted outline of the corona in figure 61 is a restoration from fragments, 

 and is possibly incorrect. 



12. Sagitta Zetesios Fowler. 



G. H. Fowler. Op. cit., p. 67. 



Three fine specimens from Station 141, well preserved in formalin, and measuring 20, 

 27 and 30 mm., seemed to be almost certainly referable to this species. The largest of these has 

 been drawn as figure 73, and exhibits a condition of fin and collarette intermediate between 

 figures 22 and 23 of the Biscayan Report. Three small and less well preserved specimens in 

 the same haul, appeared also to be attributable to the same species ; one of these is represented 

 in fio-. 74. Ten further specimens in the same haul, although at first of a different appearance, 

 yet could be placed in no other species; they were obviously very sharply contracted, judged 

 by the look of the longitudinal muscles, and especially so at the posterior end; this had given 

 them a very thick-set appearance with a stumpy tail, and had exaggerated the width of the 

 posterior fin. The outline of one of these forms figure 75, and the jaws and teeth have been 

 drawn from another of the same set, so that the similarity to Zetesios may be observed in the 

 least likely case. Precisely the same contraction, with the same results, was noticeable in many 

 specimens of Krohnia hamata from deep vertical nets. 



The remainder of the material assigned to this species was preserved in alcohol, and 

 showed for the most part the same effects of sharp contraction; but the specimens could 

 apparently be graded backwards into the large finely-preserved specimens first mentioned. The 

 tail in these contracted forms, not unnaturally, often bore a smaller proportion to the total 

 lenoth than was the case with the Biscayan specimens; and in all the Siboga specimens the 

 lateral fields seemed broader, and the posterior fin more rounded. But the coincidence of more 

 important characters is so close, that there is no necessity to found a new species on such points. 



As with the Biscayan material, even the largest specimen was far from maturity, the 

 vesiculae seminales only projecting slightly. Formulae: — 



30 





26 





7 



8 



17 





27 





25 





9 



8 



19 





2 5 





20 





9 



9 



18 





2 3 





26 





9 — 10 



8—10 



18 





2 2 





27 





8 



8 



17 





2 1 





2 1 





9 



1 1 



20 





20 



2 



7 3 







8—9 



7—10 



16 





19 



2 



1 — 2 



6 



8 — 10 



7-8 



16—] 



S 



18 



2 



5— 2 



7 



8-9 



7—9 



16—1 



8 



16 





24 





10 



8 



17 





