194 FRANCIS H. A. MARSHALL. 
firming Bischoff’s hypothesis, but he differs from others who 
hold this view in stating that a certain relatively small number 
of lutein cells arise from interstitial cells existing in the inner 
theca of the connective-tissue sheath. Van der Stricht 
differs from Sobotta, while agreeing with the present writer 
in finding mitotic division among the follicular epithelial cells 
after the follicle’s rupture. A figure is given in one of van 
der Stricht’s papers of a section of a human ovary in which 
such division is also shown to exist. It would thus appear 
that the lutein cells, at any rate, in certain mammals, do not 
arise entirely by simple hypertrophy of the follicular epithelial 
cells, but by hypertrophy accompanied by a greater or less 
amount of cell division. The very early appearance of fatty 
particles in these cells in the bat’s discharged follicle is a 
point of considerable interest to which van der Stricht calls 
attention. 
At the meeting of the “ Anatomische Geselischaft” at 
Bonn, Kopsch exhibited sections of corpora lutea from the 
sow, representing three-, six-, and ten-day stages of develop- 
ment. These preparations in a general way supported the 
follicular epithelial theory.! 
Sobotta’s account of the formation of the corpus luteum in 
the rabbit has been recently further confirmed by Cohn, who 
also obtained a series of stages by killing the rabbits at stated 
periods after copulation. Thus the development of the 
rabbit’s corpus luteum has formed the subject of experimental 
investigations by three separate observers—Sobotta, Honoré, 
and Cohn,—who have all arrived at the conclusion that the 
lutein cells are hypertrophied follicular epithelial cells. 
An important paper on the corpus luteum of the “ Marsupial 
cat,’ Dasyurus viverrinus, by Sandes shows that this 
structure is formed in a similar way in marsupials to what it 
is in the Eutheria. The theca interna folliculi is shown to be 
rudimentary in Dasyurus. Owing to this circumstance Sandes 
points out that it is easier to follow the subsequent changes 
1 Vide Sobotta, Merkel and Bonnet’s ‘ Ergebnisse d. Anat. u. Entwick.,’ 
vol, xi, 1902. 
