106 GOES, RETICULARIAN RHIZOPODA OF THE CARIBBEAN SEA. 



Syn. PDiscorbina baconica, elegans HKEN., 1875, Clav. Sz;ib. Scli. p. 76, t. 10, fig. 3, t. 9, fig. 3, t. 15, 



fig. 7. 

 eximia HKEN., ibid. p. 76, t. 15, fig. 8. 



Discorbina turbo D'ORB. et multse alise trochiforraes auctorum a rosacea forsan nou aunt, 

 distincta;. 



Discorbina valvulata 



Tab. VIII, figg. 258261. 



Although this form has been placed as a variety under Discorb. vesicularis LMCK, 

 by Messrs PARKER and JONES, it may be proper to distinguish it as a species in virtue 

 of its peculiarly formed shell. It is identical with Rosalind Binkhorsti Rss. from the 

 Maestrich-chalk, and is remarkable for the fewness and the large size of its chambers, 

 its hollowed apertural side, which is of simpler structure than usually, not being com- 

 plicated with additional asterigerine flaps, having no more than a narrow valvular 

 strip on the upper margin of the aperture. 



It attains a pretty good size, occurring only in the coralline-gravel. 



Figg. 258 259: the spiral side. 



Fig. 260: apertural side. 



Fig. 261: edge-view. 



Syn. Bosalina valvulata D'ORB., 1826, Tabl. raeth. Ann. Sc. Nat. 7, p. 271. 



D'OKB., 1839 Cuba p. 96, t. 3, figg. 2123. 



Binkhorsti Rss., 1861, Kreidetuff Maastricht; Wien. Ak. Sitz.-Ber. 1. 44, p 317, t, 2, 



fig. 3. 

 PRotalina patella Ess., 1849, Neue For. Wien. Beck.; Wien. Ak. Dkschr. 1. i, p. 371, t. 46, 



fig. 3 (an D. Berthelotiana). 



Discorb. stellata, squamula Rss., 1867, Steinsalzablag. Wieliczka; Wien. Ak. Sitz.-Ber. 1.55, p. 101, 



t. 5, figg. 1 2 (an P. rosacea). 



Discorbina bulloides D'ORB. 



Tab. VIII, fig. 262263. 



I am not able to find any satisfactory reason for a generic nay even for specific 

 distinction between Discorbina rosacea and this form, which has been referred to the 

 genus Cymbalopora (Hagenow) by Messrs PARKER, JONES and CAKPENTER, 



This however seems to have very small affinity to our form - - if any at all. 

 (See also SCHWAGER in Butchlis' Klassen und Ordnungen des Thierreichs 1881, p. 256.) 

 Prof. MOEBIUS has carried the separation from its natural relations still further by 

 assigning it a place in a new genus, Tretomphalus ; (Meeresfauna Mauritius und Sey- 

 chellen; foramf. p. 98, t. 10, figg. 69). The pores of various sizes on the last seg- 

 ment should not be regarded as a mark of generic nor of specific distinction. If this 

 globular chamber is detached, the rest will hardly be distinguished from D. rosacea. 



