318 MR. A. T. JEIWINGS OIT THE TETTE 



one of them I met with the organism under consideration. At 

 that time I bad not seen Dr. Duncan's paper, or heard of Mohiusi- 

 spongia ; but I made a note and drawing of the object as a 

 Eoraminifer of the genus BamuUna. A year or so later, when 

 working at sponges, and' anxious to know about Mobiusi- 

 spongia" I referred to Dr. Duncan's paper and found it was the 

 specimen I had drawn as a BamuUna. 



I have no doubt that my determination is correct, and I 

 believe that any student of the group would recognize its 

 foraminiferal character from the original illustration. 



It only remains to examine the evidence on which the organism 

 was referred to the Sponges, and to determine, if possible, the 

 species of Poraminifera to which it belongs. 



Dr. Duncan based his conclusions, first, on the presence of '* a 

 cellular element," and secondly, on the occurrence of spicules. 



The faint lines seen in places round the projecting spines are, 

 however, only such as are frequently observed in the shells of 

 Poraminifera, forming a sort of areolation diie either to incipient 

 cracking or to the mode of deposit of the shell-material. There 

 is no trace of true cellular structure. 



The spicules observed are two or three broken needles and 

 one triradiate. All would be far too large in proportion if 

 the body were a Sponge, and none have any actual connexion 

 with the walls of the chambers and tubes, as was admitted in the 

 original description. They are evidently entirely accidental. 



"We may therefore, I consider, safely dismiss the claims of this 

 curious organism to rank with the Sponges, and the only question 

 is whether it can be included in any of the known species of 

 BamuUna. 



The genus BamuUna was originally founded by Mr. "Wright* 

 for certain fossil fragments from the Chalk. Professor E,upert 

 Jones t subsequently placed the genus on a more definite footing ; 

 and Mr. Brady J adopted it for certain recent forms found in 

 the North Atlantic and South Pacific during the 'Challenger' 



* " Cretaceous Microzoa of the North of Ireland," Eeport and Proceedings 

 of the Belfast Nat. Field Club, 1873^. 



+ In the same publication for 1875 ; and n the ' Micrographic Dictionarj',' 

 1875. 



X H. B. Brady, ' Journal of the Microscopical Society,' n. s. xix. p. 272 ; and 

 ' Challenger Eeport,' vol. x. 



