64 STURGES. [VOL. I. 



typical cells among which these degenerating ones lie usually 

 become somewhat vacuolar and their cell boundaries may 

 partly break down so that they form a coarse reticulum in 

 which, however, examination always shows typical subcuticular 

 nuclei. 



The tissues are well preserved, so that these changes in the 

 subcuticular cells can hardly be considered abnormal ; since, 

 however, the assumption of a glandlike form is not accompanied 

 by any apparent change in cuticle or subcuticula and is fol- 

 lowed by degeneration, it seems probable that the change is 

 due to age, and the appearance of the other subcuticular cells 

 confirms this idea. One recalls in this connection the sug- 

 gestion of Looss 1(a) that the presence of the subcuticular cells 

 as a definite layer may depend upon the age of the specimen 

 studied, and the facts found here suggest that possibly their 

 glandular or non-glandular appearance may depend upon a similar 

 condition. It is difficult to compare the glandlike cells found 

 here with the glandular subcuticular cells noted by others, for 

 descriptions and figures are seldom definite enough on this 

 point; but it seems possible that they correspond to those 

 noted by Blumberg, 14 to some at least of those subcuticular; 

 cells described by Monticelli as skin glands (see Looss 1(a )), and 

 to the glandlike cells described by Poirier. 7 No degeneration 

 stages such as exist in this form are described by others. The 

 transition of the subcuticular cells into the subjacent paren- 

 chyma shows that they must be considered peripheral traces 

 of primitive parenchyma as Leuckart, Mace, Ziegler, Schuberg, 

 and Goto suggest; while their coextensiveness wjth the cuticle 

 and their ability, in some species at least, to assume a gland- 

 like form (although in D. patellare this does not seem to be 

 functional in the adult) indicate that, as Looss and E. Walter 

 suggest and Brandes and Blumberg affirm, they may have a 

 glandular function in some way connected with the cuticle. 



On the whole, the facts found in connection with the cuticle, 

 subcuticula, and subcuticular cells of D. patellare seem to me to 

 support the view that the cuticle is not a true cuticle, a modi- 

 fied epithelium, or a basal membrane, but a pseudo-cuticle 

 formed when the larval epithelium was lost. It seems prob- 



