Gfoirf/i (I ml Habits of Biporae. 7 



Kiiiall ]»(!rticin of the surface inorL' liiulily iiiatrnitied (Fi<x. 2a) to 

 show their structure more clearly ; it will be seen that the 

 ■■ raised nodular process "' appears to be a means of strengthen- 

 intr the connection between the Hap and the rest of the zoarium, 

 and I think shows the improbability of the " slit '' being con- 

 tinued, through it, into a circle, so that the Hap would fall off. 



There is yet another point I nuist notice here, and that is, 

 that in the specimen Hgured the niarginal zooecia have very 

 large inverted funnel-shaped jjeristomes, and it is a question 

 of considerable interest as to how these large peristomes become 

 absorbed, or rejected, as there is no trace of them in the older 

 zooecia. Altogether the liipurae exhibit so many abnormali- 

 ties that they are well worth further careful study, especially if 

 spirit preserved specimens of living forms can be obtained. 



EXPLANATION OF PLATE I. 



Fig L — Section of coral growing in Bipora, a to b, line of 

 junction, x- 26. 



Fig. 2. — Portion of zoarium of Bipora philippluensis, show- 

 ing ooecia and semilunar slits. x CO. 



Fig. '2a. — Portion of same zoarium, showing a thyrostome, 

 avicularia and a semi-lunar slit, x 1015. 



NOTE. 



8ince the above paper was written, I have received from Mr. 

 G. ]\L Jv. Levinsea, of the Zoological Museum, Copenhagen, a 

 copy of his " Morphological and sy.s|ieinatic studies of the Cheilo- 

 stonious Bryozoa," in which, with reference to the "semi-lunar 

 slits" (which he terms " lunoecia,"), he says that the view that 

 they are "rudiments of new zooecia " is quite incorrect and m 

 complete conflict with liis investigations on them, and that the 

 idea that new zooeci;i ctyi be intercalated between older in a well 

 calcified Bryozoa colony is so improbable that he has " no hesita- 

 tion in declaring snch a process impossible." 



