British species of the genus Lagena. 13 



tervening form between the figures 1 and 3. It is one of the most 

 elegant of the Lagenulce. 



Long. Diam. 



I 1 



To • • • • lBO 



'_ _!_ 



~U6 • • • ■ 170 



1 _1 



?5 • • • • 2 00 



Oxwich, Sandwich, Oban, J. G.Jeffreys, Esq. Boston; March. 



2. Lagena gracilis, nob. PL I. fig. 5. 



In form this species bears a very close resemblance to the L. 

 Icevis, var. Amphora, from which it differs chiefly in having its 

 surface marked by longitudinal striae, which are well defined over 

 the greater part of the cell, becoming less distinct towards the 

 upper portion. If we consider this as only another variety of the 

 Amphora, it will become necessary to regard all the forms of 

 L. striata merely as states of L. Icevis, of the propriety of which 

 view a suspicion has more than once crossed my mind when ex- 

 amining some specimens of the var. /3. semistriata. For the pre- 

 sent I have thought it better, having seen several specimens of 

 it, to give it a distinct name. If this suspicion should ultimately 

 prove to be correct, L. gracilis will bear the same relation to 

 L. striata and its var. perlucida that the var. Amphora does to 

 L. lavis. 



Lon s- tV; diam - ah- 



Boston : very rare. 



3. L. striata. PL I. figs. 6 & 8. 



Serpula (Lagena) striata, Walker, p. 2. tab. 1. fig. 6. 



Vermiculum striatum, Mont. Test. Brit. p. 523. 



Serpula striata, Turton, Conch. Diet. p. 157. 



Lagenula striata, Fleming, p. 234. 



Cell ovato-claviform or spherical, with numerous parallel lon- 

 gitudinal costse or lamellae, which generally run nearly from one 

 extremity to the other, only not usually reaching the apex infe- 

 riorly but terminating abruptly, forming a small circular coronal 

 (see fig. 7) . These costse are sometimes very thin and lamelliform, 

 but more commonly obtuse and rounded. The cell surmounted 

 superiorly by a long tubular neck terminated by a narrow rim 

 encircling the small round oral ? orifice. 



Nothing can be much more variable than the conditions under 

 which this species presents itself. In small young specimens 

 alone is the tubular neck found perfect, and these are usually 

 either transparent and hyaline or of a pale bluish white. On the 

 other hand, the specimens usually seen in the cabinets of concho- 

 logists are strong, globular, of an opake dirty white, the rounded 

 costse alone remaining semitransparent, and with very imperfect 



