No. 636] 



NOTES AM) LlTl-UATl ltK 



morphological variations of the organs, we now substitute that 

 of the physiologic functions. Our studit^ are therefore always 

 directed toward the discovery of functions which modify the 

 skeletal form." With this frank statement of the primacy of 

 the Lamarckian principle, family, genus and species are thus 

 briefly described: 



The family is characterized by the larval form. 



One genus differs from another in possessing a different func- 

 tion. The three essential functions of all bryozoa are: 



1. Passage of egg and escape of larva? (= rapport of operculum 



and ovicell). 



2. Hydrostatic system and extrusion of the polypide (=form 



of the aperture ami rappnrt of operculum with com- 

 pensatrix). 



3. Calcification and chitinization (= nature of the skeletal 



part and of the frontal considered as deposits of the 

 endocyst). 



Specific characters include all morphological variations and 

 all of the characters of adaption. 



Whatever philosophic views one may hold in regard to the 

 relation between form and function, it is apparent that the char- 

 acters chosen for family, genus and species present a uniform, 

 logical system and constitute a good workable plan or hypotliesis 

 which it seems more than worth while for all work^^-s in this 

 field to attempt to apply. It must be remembered, however, that 

 while in the class bryozoa, larval characters may afford valid 

 data indicating relationship such characters have failed to afford 

 satisfactory data of relationship among some other class of ani- 

 mals. Granting the validity of the assumption, however, the re- 

 search necessary to establish this statement can be conducted 

 only on living species. This, then, is a matter of immediate and 

 pressing interest. The older bryozoologists considered the oper- 

 culum a family character. In the present system the o[)erculuia 

 becomes a generic character, changes in it being induced )iy 

 changes in the essential zo(Pcial functions 1 and 2, that is, de- 

 pending in part upon the relation existing between the oper- 

 culum and ovicell, and in part upon the relation existing between 

 operculum and compensatrix together with the form of the 

 aperture. Here again, although much investigation has been 

 conducted to verify those grcneric priiiciph's aumiio- ilit> fossil 

 Tertiary species, work on living forms shouhl be undtTtaken to 



