EDITORIAL GLEANINGS. 355 
may perhaps be allowed to afford a working hypothesis that can be 
used in systematic study. The results of such a hypothesis would, I 
think, be far-reaching. Whether we are justified in accepting it pro- 
visionally or not, I am convinced that we require some hypothesis by 
which we may regard two specimens as belonging to the same species, 
even though they may differ in what might at first sight seem to be 
fundamental respects. And, vice versa, we require the liberty to 
regard two species as widely separated from each other in the system, 
even though they possess identical types of avicularia. There are 
other questions which might have been considered in the Cheilosto- 
mata, and, in particular, the presence or absence of oral or marginal 
spines and the forms and distribution of the ovicells. The occurrence 
of the latter is, however, probably connected with the presence in the 
young zocecium of tissue which will give rise to an ovary, and this 
implies the consideration of another factor which is very difficult to 
estimate. 
“T must not conclude without at any rate referring to the fact that 
the Polyzoa are by no means the only animals in which dimorphism 
or polymorphism occurs as the result of blastogenic processes. But 
among the Cceelenterates, for instance, the occurrence of medusoid 
individuals cannot be considered apart from the question of sexual 
cells. There is, however, one series of cases among Hydroids to 
which allusion may perhaps be made. I refer to the existence of 
pairs of genera such as Corymorpha and Tubularia, Syncoryne and 
Coryne, Podocoryne and Hydractinia, in each of which pairs the two 
genera are distinguished by the fact that one produces free medusz, 
while the other has sessile gonophores. There is already some 
evidence that the validity of these generic distinctions is open to 
question ; and the free medusoid individual and the sessile gonophore 
might conceivably be related in such a way as to form members of an 
allelomorphic pair. The same phylum contains another striking 
example of dimorphism in the distinction between gastrozooids and 
dactylozooids in many Hydroids; while in the Siphonophora the 
differentiation of various forms of individual has advanced much 
further. But I have already gone much beyond my evidence, and I 
must bring my remarks to a conclusion by expressing the view that 
the causes which regulate the differentiation of the individuals during 
the blastogenic development of the Polyzoa are well worthy of further 
study, and that our knowledge of the unity of the vital processes 
throughout the animal kingdom gives us reason to believe that they 
are part of some general biological law.” 
A most timely protest was made by Mr. G. A. Boulenger “‘ On the 
Abuses resulting from the strict Application of the Rule of Priority in 
Zoological Nomenclature and on the Means of Protecting well- 
established Names.” Disapproval was expressed of the extreme 
application of the rule of priority, which in the author's opinion had 
brought about much mischief under pretence of aiming at ultimate 
uniformity. The author protested against the abuse to which this 
otherwise excellent rule had been put by some recent workers, 
encouraged as they were by the decision of several committees who 
had undertaken to revise the Stricklandian Code, elaborated under 
