48 BULLETIN OF THE 



from a young stock what has been tlie order of succession of individuals. 

 One has to view the object from botli sides, make a careful examination 

 of the walls of the zooccia and of the relation of the polypidcs to one 

 another, and, when he has done his best to determine what are the facts, 

 he must feel that his conclusions are after all moi'c or less subjective. 

 By a careful study of the colony shown in Figure 71, I have constructed 

 the diagram shown in Figure 7 P. 



The stock of Lepralia is a creeping one, and all of its rows of individ- 

 uals are in juxtaposition. This juxtaposition is continued into the adult 

 stage. Even the young stock begins to show evidence of a quincunx 

 arrangement of individuals. This is less evident in the youngest indi- 

 viduals than in the older part of the stock, and is most evident in old 

 colonies. That there is not here a ti'ue dichotomous division of rows of 

 individuals, resulting in the aimihilation of the ancestral row and the 

 establishment of two new ones, is evident from a glance at the youngest 

 generation in rows 11, 12, or, better, 2, 3, in which the relation of ter- 

 minal (11, 3) and lateral (12, 2) individuals is very different. The for- 

 mer continue the ancestral line, the latter establish new rows. Lepralia 

 differs from Bugula in this : that two lateral branches may be given off 

 from the ancestral row in the same generation, as at B, C, and a, a 

 (enclosed in circles), Figure 71°. 



In contradistinction to the conditions in Bugula, when only one branch 

 arises, it is not given off towards the axil, but away from it. 



The synchronism of the budding process noticed in B. turrita is hardly 

 distinguishable in the adult stock of this species ; in the young, however, 

 it is quite marked, and gives to the whole a very symmetrical form. The 

 cleavage of eggs does not proceed by more regular steps. Of the three 

 individuals a, C, a (in circles), which follow B, each has given rise to 

 three otiiers, a median and two lateral. From each of the three individ- 

 uals derived from the two individuals a, a (in circles) has arisen a 

 lateral branch. Rule 3 is therefore well marked in the young stock of 

 Lepralia. 



Rule 4, concerning the greater frequency of lateral budding at the 

 margin, is also exemplified in Lepralia. The ratio of cases of lateral 

 to median budding being 1:1 on the margin (rows 1-G and 15-19) 

 and 1 : 2.8 in the middle (rows 7-14.) 



In Bugula, as will be recalled, it was concluded that the marginal 



what from those of older ones. Yet it is an Escharine closely allied to Lepralia, and 

 I have seen in some cases the hroad-based spine on the proximal border referred to 

 hy Verrill as being found in ly. I'allasiana. 



