476 ENTOGONIA. 



Valve triangular, with straight margins, three terminal processes slightly 

 elevated, separated hy nerve-like lines from the median portion and having in 

 addition, here and there, some nerve-like lines which extend across the valve 

 entirely or partially. Structure cellular ; cells irregular, gradually diminishing 

 towards the margins and the processes, which are punctate up to the end. 

 Girdle face much broader than the length, showing 3 to 4 costoe, with 

 undulated margins, cells small, in longitudinal rows, about 12 rows in 1 c.d.m. 

 Connecting zone very narrow. Frustules usually united in twos. Length 

 of valve, 4*5 to 5 c.d.m. 



Marine. Rather frequent. Blankenberghe, Antwerp (Scheldt). England (W. Sm., Capron, 

 Kitton, Norman, W. Arn. !). Courseules, France (Br6b.). Holland (Suringar). Ireland 

 (O'Mearaj. 



B. sculpta (Shadb.)H. Van Heurck. {Trkeratium scuiptum 



Shadb., T.M.S., 1854, ii., pi. 1, f. 4; H.V.H. Atl., pi. 109, f. 7 and 8* ; Type 

 No. 502), plate 21, fig. 645. 



Valve triangular, with straight sides, three terminal processes slightly 

 elevated ; structure cellular, cells irregular, of almost equal size throughout the 

 valve ; processes finely punctate. Girdle face longer than the breadth ; valve 

 portion undulated, with cells arranged in longitudinal rows ; 6 lines in 1 c.d.m. 

 Connecting zone rather broad, having 7 or 8 longitudinal rows of coarse dots 

 in 1 c.d.m. Length of the valve margins, about 4 c.d.m. 



Marine. Rare. Antwerp (Scheldt) ; Potter's clay from Ostend (Deby) ; Sweden (Lagerstedt). 



I think this form has escaped collectors, and will be found elsewhere. 



GENUS 133. ENTOGONIA GREV, 1863. 



Valves angular, usually with three angles' 

 leaving at the centre a smooth portion, with 

 the marginal portion divided into compart- 

 ments by false costae, which correspond with 

 internal septa ; angles of the valve more or 

 less elevated into processes. 

 ' S ' ^inopinata The genus Entogonia includes about 20 species, 



all fossil, and found especially in the deposits from Barbadoes and Jeremie 

 (Hayti). I give in the text (fig. 207) E. inopinata Grev., from the Cambridge 

 Estate (Barbadoes). 



The genus Habergia, according to Mr. Bergon, should be suppressed ; the 

 genus being in his opinion founded only on a biangular form of E. Davy a na 

 Grev. 



