BY E. F. HALLMANN. 303 



almost completely packed throughout with the shells of operculate 

 Cirripedes, and I cannot understand how, under the circum 

 stance, Lendenfeld was able to speak with confidence concerning 

 the arrangement of the canals One can only assume that he 

 looked upon the inclusion of the shells as fortuitous, and on that 

 account scarcely worthy of mention, and that his opinion regard- 

 ing the canal-system was arrived at by inference rather than 

 actual investigation. The most considerable mistake, however, 

 made by Lendenfeld in connection with this species, lies in the 

 fact that a specimen of it has been figured by him in the Cata- 

 logue (PI. i., fig.l) as Papillina panis. 



In agreement with the description of the species, the type- 

 specimens are massive, irregular, more or less laterally expanded 

 {i.e., depressed) sponges of moderate size, are covered with papillae 

 (of variable size and distribution), are of a yellowish-white colour 

 in spirits, and (in some cases) exhibit circular oscula-like openings 

 scattered irregularly over the surface. Lendenfeld sa3^s of these 

 openings, or " vents " as he terms them, that they are not true 

 oscula, but " lead into a system of vestibular lacunae which 

 occupies the interior of the sponge " : in view of the fact that, in 

 almost all other respects, the specimens afford practically indis- 

 putable evidence of their identity with Papillissa lutea, I venture 

 to say that, as regards the nature of the "vents," Lendenfeld 

 was entirely in error. In every case, I have found that these 

 openings are situated each immediately above the orifice of an 

 inhabited Cirripede-shell; and it is clear that they are simply 

 the means whereby the crustaceans maintained communication 

 with the exterior. All indications point to the fact that, with 

 continued growth of the sponge, these openings gradually become 

 closed over and finally disappear from external view.* It is 



* At the time of writing the above, I was inclined to attach some im- 

 portance to the presence of these Cirripedes, thinking it likely that the 

 case was one of regular symbiosis; but I iiave since observed sporadic 

 occurrences of a similar association in vaiious species. Owing to the 

 abundance of these shells in the specimens, 1 have not been able to deter- 

 mine, with certainty, whether C. lutea ipossesses anything analogous to the 

 trabecular skeleton of C. hixonii or not. 



