78 BULLETIN OF THE 



in which the heavy asterisks represent the budding tips of the stock, 

 which give rise to new individuals (tips of the stolons), and a^, /3j, etc. 

 indicate individuals of the fourth order. The lighter asterisks indicate, 

 as before, points of proliferation from which new buds may arise. 



It seems highly probable that Victorella finds near allies in Mimosella 

 and other genera of the Stolon ifera. 



In Hypophorella expansa, according to Ehlers ('76, pp. 5-9) and 

 Joyeux-Laffuie ('88, pp. 137-139), the stolon is composed (as in Vic- 

 torella), of a number of internodes, each separated from the other by 

 communication plates, and bearing on the distal end typically a feeding 

 zooid (Nahrthier) and a lateral stolon. It seems to me that the jointed 

 condition of the stolon is reasonably accounted for in the same way as 

 that of Victorella, by supposing that each internode, together with its 

 zooecium, is comparable with the whole indvidual of Paludicella. The 

 " feeding zooids " of Hypophorella will then be comparable with the 

 Cylinderzelle of Victorella. Two facts are opposed to this view : first, 

 the polypide is not formed primarily in the stolon, coming only secon- 

 darily to lie in the Cylinderzelle as in Victorella ; and, secondly, there is a 

 Rosettenplatte in Hypophorella between the feeding zooid and the stolon, 

 while none exists in Victorella. But upon this assumption one can best 

 account for the fact that the stolon is composed of as many joints as 

 there are feeding zooids, — a condition which appears to occur in only a 

 few other genera, and these closely allied to Victorella. Thus, in Cylin- 

 droecium pusillum and C. dilatatum of Hincks we have two species which 

 may be considered to represent two possible intermediate stages between 

 Victorella and Hypophorella, not only on account of the jointed stolon, 

 but also on account of the enlarged distal end of the joint, which is emi- 

 nently characteristic of the allies of Victorella. The first objection, that 

 the polypide is not developed in the stolon, but first arises in the well 

 formed zooecium of the feeding zooid, might result from the increased 

 importance of the zooecium over the Cylinderzelle. The formation of the 

 plate betw^een the zooecium and the stolon might be accounted for by 

 the physiological need of such an organ resulting from the increased im- 

 portance of the zooecium (cf. p. 40). Such plates exist, in fact, between 

 the primary median individuals, and those secondary median ones in 

 Victorella which are budded from the Cylinderzelle. This hypothesis 



far as they go, may not fit the conditions in all parts of the colony. Moreover, it 

 is to a certain degree idealized, i. e. subjective, for even in the figure of Kraepelin 

 ('87, Fig. 75) one of the individuals of the series a, b, c, etc. has given rise to no 

 stolon as its first bud. 



