1890.] NEW-YORK MICROSCOPICAL SOCIETY. 49 



the first small, rounded, and scarcely larger than the next, from which 

 externally, it does not appear to be separated. The remaining chambers 

 increase upward gradually in breadth, with unequal sides. The ventral 

 side is some»rhat more ventricose than the dorsal side, and is separated by 

 very small and shallow oblicjue sutures. On the concave dorsal side, all 

 the chambers are united, as it were, by a small, narrow, smooth, slightly 

 elevated ridge, upon which the division of the chambers is scarcely vis- 

 ible. The first chamber shows a slight tendency to curve forward ; the 

 last, which is very oblique, ends at the dorsal angle in a short thick spine. 

 Very rare. 



3. D. Sleenstrupi, Rss. See page 326. Very rare. 



4. D. conjiuens, N. sp. PI. vii. fig. 5. The shell (Gehause), which 

 may be 3 mm. long, is rather thick, slightly bent, sometimes compressed, 

 and consists of seven chambers, in the first of which the boundaries are 

 not to be made out from the external appearance. Only the last chambers, 

 which are slightly higher than broad, are marked off by very shallow 

 sutures. They decrease in size downwards, but slowly, the lower ex- 

 tremity however, diminishing abruptly to form the short spine, the latter 

 being sometimes directed backwards. The ciiambers are covered with 

 16-20 very narrow abrupt, longitudinal ridges, these are often irregularly 



sinuous, and increase in number, from below upward, by the insertion of 

 new ones, or, by bifurcation, they are separated by narrow deep furrows 

 between them. The last, very oblique, chambers run out into a very 

 short spine which almost points backward. Very rare. 



b) FrondicularidE'V (m.) 

 Flabellina, d'Orb. 



Fl. coniata, Rss. Sitzungsber. d. k. Akad. d. Wiss., xl. 216. Very 

 rare. 



2. CRISTELL\R[DEA, Schltz. 



Cristellaria, Lam. 



a) Marginulina, d'Orb. 



M. ensis, Rss. Die Verstein. der bohm. Kreideform., i. 29, pi. xii. 

 fig- 13. pl- xiii. figs. 26 ,27. Very rare. Frequent, however, in the up- 

 per cretaceous of other countries down to the " Planer." England, West- 

 phalia, Bohemia, Galieia, etc. Sitzungsber. d. k. Akad. d. Wiss. in 

 Wien., xl. 207. 



b) Cristellaria, d'Orb. • 



1. C>: intermedia, Rss, var. Die Verstein. der bohm Kreideform., 

 i. 33, pi. xiii. figs. 57, 58, pi. viii. fig. 2. The American specimens differ 

 from the Bohemian in forming a more distinct and larger spiral, and in 

 having the last chambers separated by deeper sutures, while the limits of 

 the first ones are not externally visible. Very rare. 



2. Cr. BavUi. N. sp. PI. vii. fig. 7. Diameter 0.77 mm. Shell cir- 

 cular, moderately compressed, lens-shaped, with a sharply, keeled dor- 



