SCAPHANDER. 249 



produced posteriorly. In the former characters it resembles Philine 

 Loveni Malm, as figured by G. O. Sars, but is still more pointed be- 

 hind, and the free margin is of quite a different shape. (Dall). 



Adults of this species were taken at station 2376 by the U. S. 

 Fish Commission in 324 fms. The shells alone were received. They 

 are the American analogue of the European Scaphander lignarius, 

 which they resemble more closely than any other species, but from 

 which they can be distinguished by their uniformly more slender 

 and cylindrical form and greater posterior attenuation. These dif- 

 ferences hold good for the young as well as the adults. The outer 

 lip generally rises higher, and the space on the posterior end of the 

 spire is less wide and excavated in S. watsoni than in the other 

 species, but these characters vary somewhat in both species. I 

 doubt if S. watsoni ever reaches the size of the Mediterranean form ; 

 the largest I have seen measured 38*0 mm. long by 19'0 mm. in 

 greatest diameter. S. lignarius of the same length generally meas- 

 ures about 24'5 mm. in diameter. 



The magnificent S. nobilis Verrill, first dredged in 1209 fms., off 

 Delaware Bay, was also found in the Gulf of Mexico by the U. S. 

 Fish Commission in 1639 fms., at Station 2127. 



S. NOBILIS Verrill. PI. 32, figs. 31, 32. 



Shell large, swollen, stout, broad-ovate in outline, thin, translu- 

 cent, and of an exceedingly delicate texture. The body-whorl is 

 very large in proportion to the rest of the shell. The aperture is 

 large, broad-ovate in the anterior part, narrowed and curved poste- 

 riorly, extending to the apex of the shell, where it terminates in a 

 notch, the outer lip extending back considerably beyond the notch. 

 The aperture is much encroached upon by the convexity of the 

 body-whorl, but about the middle the inner lip is strongly excav- 

 ated and forms a broad and somewhat sinuous curve ; the outer lip 

 is very broadly and evenly rounded throughout most of its extent ; 

 anteriorly the curvature forms the arc of a circle; posteriorly it ex- 

 tends back beyond the apex of the shell in the form of an obtuse and 

 slightly everted process, with its posterior margin concave, somewhat 

 sinuous and spiral, and a little thickened. The surface is smooth 

 and polished, somewhat shining, and everywhere covered by spiral 

 lines formed by series of oblong dots, which are decidedly sunken 

 below the surface and separated by intervals about equal to or less 

 than their own length. The spiral lines are unequal in fineness, the 



