62 
D. D. CUNNINGHAM. 
■granular contents, and, as a rule, considerably exceed the sur- 
JFig. 3. — Deep layer of epidermis, x 180. a, a. Granule cells, 
b. Empty cell-space. 
The granules with which they are filled vary somewhat in size 
in different cases, in some being very coarse, and in others fine 
and molecular ; when in mass they appear of a dark yellow or 
brown colour. In addition to these cells or cell spaces, for in 
many instances there seems to be no evidence of any distinct 
cell membrane, blank spaces or hiatuses in the continuity of the 
layer of cells present themselves here and there, which in size 
and form so exactly resemble the cells containing the granular 
matter as at once to suggest the idea that they owe their origin 
to the discharge of the contents from such structures. 
The nature of the contents and the phenomena of development 
of these granule cells was carefully investigated, and I believe 
that there can be no doubt that they are merely epithelial cells 
which have undergone fatty change and which are ultimately 
removed to make room for new structures. At first sight they 
recall the Schleimzellen originally observed by Leydig in the 
integument of fish and amphibia, and subsequently described by^ 
various other authors, and specially by Eranz Schultze and 
Langerhans.^ Such cells are generally regarded as unicellular 
glands, which, according to some observers, discharge their 
secretion on the surface ; according to others they never reach 
the surface, but by means of their thick mucoid secretion assist 
in effecting the desquamation of the older layers of epidermis. 
The granule cells in the present case resemble the Schleim- 
zellen ” in being modified epithelial cells, but here the resem- 
blance ceases. They differ entirely from the Schleimzellen 
^ “ Ueber die Haut einiger Siisswasserfische.” Von Dr. Franz Leydig. 
‘ Zeitsclirift fiir wissenschaftlicbe Zoologie/ Bd. iii, S. 2, 1851. “Ueber 
Organe eincs seclisten sinnes.” Von Dr. Franz Leydig. ‘ Verhandlungen 
der Kaiserliclien Leopoldino-Carolinischen deutschen Akademie der Natur- 
forschcr,’ Bd. xxxiv, Dresden, 1868. “ Epitliel iind Driisen-Zellen.” Von 
Franz Eilliard Schultze. ‘Archiv fiir Mikroskopisclie Anatomic,’ Bd. iii, 
S. 137, 1807. “Ueber die Haut der Larve von Salamandra maculosa.” 
Von J)r. Paul Langcrhans. ‘ Archiv fiir Mikroskopisclie Anatomic,’ Bd, ix 
rounding cells in size {vide fig. 3). 
a 
S. 745. 
