392 Mr. H. J. Carter on the tm . Appendages 



length of the tubiilar prolongation in C. latitenta^ together 

 with the consequently greater interval between the union of 

 the cirrous appendage and the chitinous coat of the statoblast, 

 enables one to examine these parts under the microscope much 

 more satisfactorily than in C. tenosperma^ where their com- 

 parative shortness brings them close together, and thus ren- 

 ders their points of union more or less indistinct (' Annals/ 

 I. c. pi. xvii. fig. 1). 



Identical, however, as the cirrous appendages in the species 

 of Spongilla are, I have not been able to trace any connexion 

 between them and the interior of the tubular prolongation in 

 C. latitenta^ although in the rounded or cord-like portions 

 an axial line may occasionally be discerned as in the iilament 

 of C. tenosperma. 



Nor have I shown any union of this kind in my diagram of 

 these parts in C. tenosperma (' Annals,' I. c. pi. xvii. fig. 2), 

 although in the description it is assumed, from the axial line 

 at the end of the cirrus widening, and its granular contents 

 coming so near the like material in the tubular prolongation 

 of the chitinous coat ; for in the diagram, which is meant for a 

 vertical section, the line "c?" is made to circumscribe the 

 tubular prolongation, which would not have been the case had 

 my inference, as it now appears, been as truthful as the re- 

 presentation. 



But the question here is not so much whether the axial 

 cavity of the filament has a direct communication with that of 

 the tubular prolongation, as Avhether the " glairy, fatty- 

 looking globules " in the former are derived from the " ger- 

 minal contents of the statoblast," all of which seems to be 

 satisfactorily negatived by the form and disposition of the 

 cirrous appendages in G. latiienta. Hence my premises in G. 

 tenosjjerma {op. et I. c.) are worthless, and the argument based 

 on them becomes an unfounded assumption. 



I have alluded to the statoblasts of Prof. Leidy's Pectina- 

 tella magnijica, some of which Mr. Potts kindly sent me for 

 germination ; and I can see distinctly under the microscope an 

 axial line of particles in the terminal branches of their cirri 

 similar to that in the cirrus of G. tenosperma (fig. 6, d) ; so 

 that the identity in structure and composition between the 

 statoblast of Spongilla and that of the so-called " winter-egg " 

 of the Bryozoa, which I endeavoured to show twenty-two 

 years ago ('Annals,' 1859, vol. iii. p. 331, pi. viii.), is now, 

 as Mr. Potts has stated (Proc. Acad. Nat. Bci. Philadelphia, 

 Dec. 6, 1881, p. 460; and < Annals,' April 1882), thus "ren- 

 dered more complete " — a fact which may tend to make the 



