No.1.] BUDDING IN GOODSIRIA AND PEROPHORA. 193 
That Kowalevsky failed to make out the precise relations 
between the bud and the septum of the stolon is not surprising, 
since he studied whole buds almost exclusively ; at least he 
could have had no complete series of sections. The septum is 
very delicate, and is entirely surrounded by tissues denser than 
itself, and for these reasons it is almost, if not wholly, impossi- 
ble to trace the actual condition of things in the living bud. 
But the failure of Wan’ Beneden et. Julin, and of Pizom)'I 
cannot account for so easily, since these authors made use of 
thin sections in their studies. It seems probable that they 
either missed the stages in which the facts are most easily 
seen, or that their series of sections were imperfect. Under 
other circumstances it appears hardly possible that they would 
have overlooked the facts, patent as they are. 
It would appear that Van Beneden et Julin, having care- 
fully followed through its entire development the bud of 
Clavelina, and having studied the bud of Perophora sufficiently 
to see that in most particulars it agreed with C/avelzna, thought 
themselves safe in assuming the same agreement would hold in 
all points. So many common characters do the two genera 
present, not only in adult structure but also in development, 
both of embryozooids and blastozooids, that such an assump- 
tion might very naturally seem warranted. The case furnishes 
only another illustration of the dangers to which morphologists 
are subject when they assume certain things to be true of one 
animal because they are known to be so for another closely 
related one. The fatality lies most frequently, I suspect, in 
the supposed, and not real, close relationship between the 
animals. 
These authors practically, though unconsciously, say that their 
observations on this particular point are defective for Pevophora. 
They say (p. 307), “nous n’avons pas pu nous édifier complete- 
ment sur l’histoire du coeur et du systéme nerveux,” etc. 
Now, as will appear from my account of the development of 
these organs, it would have been well-nigh impossible for them 
to fail of a clear understanding of the development and relations 
of structures mentioned without likewise missing the true rela- 
tions of the bud to the stolonic septum. 
