178 NEW YORK STATE MUSEUM 



Orbulina universa d'Orbigny 



Plate 4, figures 10-13 

 Orbulina universa d'Orbigny, 1839, Foram. Cuba, p. 3, pi. i, fig. i 



We have stated that Orbulina universa appears to lack 

 an orifice, and that thousands of specimens examined by Brady in 

 his Challenger Report material failed to discover any with such 

 opening. D'Orbigny, in his early reports, states that he found such 

 openings, but only on about one-sixth of the material examined. 

 We surmise that such openings existed only in fossil types, due to 

 some weak development of the test and not to biologic design and 

 permanent physiologic feature. 



•There are many minute, and a few large, nearly circular cross 

 sections of Orbulinae on these chert slides; but not all are true 

 sphe"es such asO. universa calls for. These are probably more 

 numerous than our survey shows, for some may be cut away from 

 the center and some may have been originally slightly unsymmetrical. 

 Examples appear to be shown best developed on slides 2, 3 and 6, 

 and a two-chambered form, doubtfully placed here on slide 2 (also 

 slide 6) . It is entirely possible that Globigerina bull- 

 o i d e s cut near its ultimate segment would reveal a similar outline 

 in section. We consider, however, the type to be present in all 

 material studied. 



Genus GLOBIGERINA d'Orbigny 



The genus Globigerina, by far the most abundant and widespread 

 of the pelagic Foraminifera of today, represents a well-circumscribed 

 distinct group of involute, somewhat globular-chambered forms. 

 Orbulina is the simplest type of the larger family which by multi- 

 plication of segments becomes most complex in G. cretacea. 

 It is, like Orbulina, known in the Cambrian, and there is seldom 

 any report upon fossil Foraminifera of any age which does not 

 reveal this genus. In the fossil world, however, .it is not well 

 represented specifically, most forms being placed under a very few 

 species of which the entire known series is relatively small. We 

 have, however, in the Bonaventure cherts a remarkable develop- 

 ment of Globigerina, and it is present in every section examined. 

 Moreover, there is a wide divergence in size, segmentation and in 

 variety of species which we could hardly look for in so early a 

 formation. Many of these types appear to be identical with the 

 forms described by Matthew in the Canadian Middle Cambrian 

 of Hanford Brook, St Martin's and it is not unlikely that some of 



