296 



and in both cases the proximal rim of the aperture runs out into a stout ros- 

 trum directed somewhat distally. 



This species which occurs along with "Schizoporella' sdntillans incrusts like 

 that species oyster shells, from Stewart Island (Miss Jelly). It is nearly related 

 to Rhijnchozoon bispinosum and ^Schiz.< sdntillans, which must likewise be referred 

 to the genus Rhijnchozoon, and to judge from the species mentioned this genus 

 seems to be characterized by the possession of a more or less well-developed 

 sinus on the aperture, by its ocecia which have an entire frontal surface and 

 are provided with an incomplete ooecial cover and by the possession of pore- 

 chambers. In Rhync. sdntillans however the operculum is provided with a strongly 

 developed accessory part, the hinge-teeth not being in connection with the inner 

 surface of the operculum but with its free margin. 



Family Myriozoidae Smitt., char, emend. 



The zooeda, provided with a covering-membrane and more or less thick-walled, 

 always lack spines and are furnished with numerous, sometimes more scattered, 

 sometimes more closely placed pores, which in the very thick-walled forms 

 appear as long canals. Both the distal wall and the lateral walls which are com- 

 mon to the adjoining zooecia are provided with uniporous rosette-plates, which 

 usually occur scattered, more rarely in uniporous pore-chambers. Dependent avi- 

 cularia seem always to be present. The oada are as a rule hyperstomial and con- 

 sist of two calcified layers free in their whole extent. They arise from a broad 

 proximal part, are immersed in niche-like depressions and their frontal wall is 

 covered and as a rule quite concealed by an ooecial cover originating from the 

 cryptocyst of the higher situated zooecium. More rarely they are endozooecial. The 

 colonies are seldom incrusting, as a rule free, usually branched with cylindrical 

 branches, sometimes laminate. 



Busk has instituted a genus Gephyrophora, and the most significant part of 

 the generic definition is the following: »A prominent avicularian process on each 

 side of the orifice, the two eventually inarching and forming a bridge in front 

 of it«. This character, however, is not sufficient for the establishing of a new 

 genus, as the bridge named is identical with that found in the species of the 

 genus Haswellia. In the genus Adeonella as well as in the genus Haswellia the 

 peristomial pore is formed in such a way that two peristomial processes unite to 

 form an arch in front of the aperture. In Hasw. australiensis, Hasw. auriculata 

 and Gephyrophora polymorpha each of these processes is provided with an avicu- 

 larium, but while this in the two former species is very small in proportion to 

 the process on which it is seated, it is in the latter so large that the process may 



