124 SIDNEY F. HAEMER. 



parts perfectly white growing points or new apertures were 

 making their appearance. Similar phenomena of regeneration 

 have been repeatedly observed in all the species which I have 

 examined. Thus the first glance at an ordinary colony of C. 

 ram OS a will suffice to show that the tubular ends, so charac- 

 teristic of the young zooecia, are absent in the lower parts of the 

 colony, where they have been either broken oflF or absorbed. The 

 zooecia which are in this condition are closed by an obliquely 

 placed diaphragm, as described in Crisia and other Cyclo- 

 stomata by Waters,^ Pergens,^ and others. On staining a 

 specimen of C. ramosa without decalcification, it is at once 

 obvious that these diaphragms are used for the closure of 

 zooecia which contain brown bodies but no functional polypides. 

 They are placed at the point where the zooecium normally 

 becomes free from the internode, and the free portion becomes 

 gradually broken away or absorbed down to the point where 

 the diaphragm is situated. In the younger parts of the colony, 

 where the zooecia possess free tubular ends, no diaphragms are 

 present, and functional polypides or obvious buds, together 

 with the brown bodies formed by the death of the last poly- 

 pides, are found in nearly all the zooecia. 



The individual life of the zooecium has not, however, neces- 

 sarily come to an end with the formation of one of these 

 diaphragms, as may be easily proved by the examination of 

 suitable spring colonies which have been stained with borax 

 carmine without decalcification. Whilst zooecia in which no 

 regeneration is taking place are closed by a diaphragm and 

 appear perfectly unstained, the red colour of the regenerating 

 parts is obvious at the first glance. The first indication of the 

 renewed activity of a zooecium is given by the fact that some 

 of the cells below the diaphragm have acquired the power of 



* A. W. Waters, "Closure of the Cyclostomatous Brjozoa," 'Linn. Soc. 

 Journ. Zool.,' vol. xvii, 1884, p. 400; "Fossil Cjclostomatous Brjozoa from 

 Australia," 'Quart. Journ. Geol. Soc.,' vol. xl, 1884, p. 675. 



^ Ed. Pergens, " E-evision des Bryozoaires du Cretace figures par d'Orbigny," 

 1« partie, " Cjclostomata," ' Bull, de la Soc. Beige de Geol.,' &c., tome iii, 

 1889, p. 317. 



