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fibrils, since tlie latter can also be seen in those cells which 
also contain keratohyalin granules. 
Schridde emphasises the necessity of using very thin 
sections, not more than 5/*, to make out the proper course of 
the fibrils in the cytoplasm. Although it is quite probable 
that the path of the fibrils follows definite lines, yet it must be 
noted that Schridde’s observations on this point have not 
been confirmed by other workers. 
Other authors who have dealt with the epidermal fibrils 
are Weidenreich, Rabl, Nussbaum, and Rosenstadt. It will 
be necessary only to refer to the work of the latter. 
Roseustadt (191.0) pointed out that the idea of the earlier 
writers that the prickle-cells are joined to each other by 
protoplasmic bridges is erroneous. He asserted that the 
epidermal fibrils are the only nexus between adjacent prickle- 
cells. 
The thickening in that part of each fibril which lies between 
two adjacent cells is not due, he thinks, to the presence of a 
nodule, as described by Ranvier, but is an optical effect pro- 
duced by the fibrils which cross other fibrils in a direction 
perpendicular to the plane of section. 
McConnell (1908), in an examination of 100 malignant 
growths, determined the presence of the fibrils distinctly in 
34, all of which were squamous epitheliomata. On the other 
hand, in 22 rodent ulcers, 25 carcinomata and 6 sarcomata 
the fibrils were entirely absent. 
The Epidermal Fibrils in Relation to Chondriosomes. 
It is to be observed that none of the authors quoted above 
has indicated any connection between the fibrils and chondrio- 
somes. 
Nor is this surprising, when it is remembered how recent is 
our knowledge of the latter cell structures. 
Von la Valette St. George (1886) described a structure in 
the spermatids of insects, to which he gave the name of 
Nebenkorper, and which he showed was built up of granules 
