BULIMINIDAE 135 



260. Bulimina inflata, Seguenza (F 132). 

 Two stations: 180; WS 517. 



A single specimen at each station. 



261. Bulimina buchiana, d'Orbigny (SG 173). 

 Six stations: 385-7; WS 204, 205, 469. 



Rare at St. 386 and very rare elsewhere. All the stations are in the deep water of the 

 Drake Strait and Scotia Sea, between 3102 and 4773 m. 



Genus Delosina, Wiesner, 1931 



Polymorphtna } complexa, Sidebottom, 1904, etc., RFD, 1907, p. 16, pi. iv, figs. 1-9, text-figs. 



3-7- _ 



Delosina, nov. gen., Wiesner, 1931, FDSE, p. 123. 



When Sidebottom first described P. ? complexa he was "much puzzled as regards the 

 genus of this species ", a feeling which has been shared by all workers who have met with 

 the form in subsequent years. He corresponded with me at intervals on its affinities, and 

 in 1922 was definitely contemplating a paper establishing a new genus, Delosina, for its 

 reception. His chief difficulty lay in the material available. Specimens were few in 

 number, they were too small and thin-walled to section, and owing to some qualities 

 inherent in the material of the test, Polymorphina complexa does not make good trans- 

 parent preparations. For such a thin-walled test balsam preparations are very opaque 

 and difficult to resolve. I think these factors even more than advancing years caused 

 him to abandon the project, for in February, 1923, he wrote: " I shall not bother about 

 P. complexa, and shall send you the slides of a paper I had thought of publishing. You 

 can do what you like with them". The "paper" had got no farther than a record of 

 published references, and as the slides threw no additional light on the subject, they 

 were placed in the Heron-Allen and Earland collection, to await the time when more 

 material should be available. 



In subsequent years no attempt has been made to settle the systematic position of 

 P. complexa. Cushman and Ozawa did not include it in their revision of the genus 

 Polymorphina, merely stating (C. and O. 1930, P, p. 16) that " it has the same arrange- 

 ment of chambers as Giittulina, but it has pores along the suture lines, and the aperture 

 is quite different from any genus of the family. It may be a new genus belonging to 

 some other family". 



Wiesner found specimens in material from the "Winter Station" of the German 

 South Pole Expedition, and in 193 1 by a happy coincidence established the new genus 

 Delosina for his organisms, using the name Sidebottom had chosen and for the same 

 reason, Delos being the first recorded locality. Wiesner figures two distinct forms, both 

 ascribed to Sidebottom's species, which he differentiates as "slender" and "broad", 

 and gives no definition of his genus, stating only that " The slender shells are like those 

 of Polymorphina, the broad ones sometimes have the chambers most irregularly as- 

 sembled. The needle-stitch-like apertures are sometimes situated at the aperture surface 

 of the chambers, sometimes on the sutures. The last of these apertures (i.e. those on the 



