388 Froceedi ii</8 of the Bot/nl Society of Victoria. 



side, not always on the same side, and which is not always 

 present ; one specimen showed only two or three avicularia, and 

 these had longer mandibles than the type, and the umbos were 

 smaller. 



Schizopopella hetenomoppha, nov. sp. (Pi. Figs. 4-6). 



Adult zooecia indistinct, covered with large tubercles, more 

 or less confiuent, some of which i>roject over the thyrostome 

 completely concealing its form, a row of perforations down 

 each side of the zooecium indicating its limits. Some of the 

 tubercles bear pointed avicularia on the summit. The young 

 zooecia are ovoid in shape, ventricose ; surface with a few 

 rounded grtinulations ; a row of poi'es round the lateral margins. 

 Thyrostome transversely elliptical, with a broad sinus in the 

 proximal margin. Ooecia small subglobular, surface sometimes 

 entire but generally composed of large, more or less confiuent 

 tubercles. 



This is a very variable species. It is only in the young cells 

 that the thyrostome is visible. One is shoA\'n at Fig. 4. In 

 older zooecia the tubercles are crowded, and sometimes the rows 

 of marginal pores are very clearly seen, more so than in that 

 one shown in Fig. 5, which is taken from the same fragment as 

 Fig. 4. The oldest form of zooecia is shown in Fig. 6, which 

 also bears ooecia : the tubercles in several places are surmounted 

 with pointed avicularia and the marginal pores are very 

 irregular, only occasionally indicating the margin of the zooecia 

 It w'ould require a great many figures to show all the variations 

 which occur in this species. In the collection sent to me by 

 Dr. Porter there were nineteen mounted specimens, and they 

 were so variable that I at first thought there were several 

 species. Figs. 4 and 5 are taken from the same specimen, from 

 which it will be seen that the variation in a single specimen is 

 very great : there are intermediate forms also in it. In some 

 of the specimens, although the surface was crowded with 

 tubercles, yet the row of marginal pores were almost as regular 

 as in the young zooecia ; in others they were not so regular, 

 and, as shown in Fig. 6, they are sometimes very irregular, 

 owing to their being overgrown with tubercles ; but they were 



