THE ALCYONARIA OF THE CAPE OF GOOD HOPE AND NATAL. 585 



In the contracted condition, the autozooids have the appearance of a more or less 

 circular swelling (the calyx), which is divided by eight radial lines into eight portions. 

 These lines extend inwards and upwards from the circumference of the circular swelling 

 to the opening of the autozooid, where the tips of the pink tentacles appear. These 

 radial lines are evidently the basis of longitudinal lines which are seen on expanded 

 autozooids. The mouth of the contracted autozooid generally stands open, and has an 

 oval form. On contraction, the tentacles appear to be drawn downwards, but are 

 apparently not inverted. Each autozooid is firstly surrounded by an irregular ring of 

 single siphonozooids, but beyond this " annulus " other siphonozooids occur irregularly 

 scattered. The siphonozooids also show an eight-partite arrangement similar to that seen 

 in the autozooids, but the former are much smaller, the largest measuring about 1 mm. 



The muscles in the upper part of the autozooids are very largely developed, but are 

 smaller in the basal portion. The mesenterial filaments of the autozooids are very large, 

 and are grouped into a number of lobes at the internal end of each mesentery. The 

 occurrence of cilia was not observed in the siphonoglyphes of the autozooids. The 

 cavities of the autozooids are continued directly downwards into canals in the ccen- 

 enchyma, and so on into the stipe or trunk. 



The opening of the siphonozooid leads into a thick-walled stomodseal tube, which is 

 continued into a larger and wider cavity with thin walls. The stomodseal tube is pro- 

 vided with a wide groove containing a remarkably large number of cilia. In a 

 longitudinal section through the ciliated groove, the cavity appears to be completely 

 filled with cilia. 



Transverse sections through the "pileus" show that the ciliated grooves of the 

 siphonozooids are not directed similarly as regards the colony, but are turned in various 

 directions. The muscles of the siphonozooids are feebly developed. 



The siphonozooids appear to increase in number by a process of binary fission. In 

 several transverse sections through the siphonozooids, one observes an ingrowing 

 swelling of the lateral wall of the stomodseum on each side. These infoldings of the 

 stomodaeal walls tend to meet one another in the centre of the cavity. Thus the 

 division does not take place from the dorsal and ventral walls, i.e., not from the ciliated 

 groove and opposite wall. 



A noteworthy feature of both specimens was the occurrence in the large canals of 

 the trunk of structures, which appeared to be embryos at the gastrula stage of develop- 

 ment. As I have only two examples of this interesting species, I am unable to pursue 

 any further study of these embryos, or wider research on the anatomy of this interest- 

 ing form. 



Locality, etc. :— P. F. 15,888 and 15,888b. Off Seal Island, False Bay, S.W. 

 I- S. f mile. By dredge. Depth, 11 fathoms. Nature of bottom, rocky. Date, 

 November 12, 1902. 



