ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
507 
Development 'of Oviducts in Man.* — Dr. P. Wendeler traces the 
development of the oviducts from their beginning in the fifth week of 
embryonic life. The material for the formation of the Mullerian ducts 
is the coelomic (archinephric) epithelium. The tube grows backwards 
between the Wolffian duct and the thickened superficial epithelium of 
the Wolffian body. Its growth depends mainly ou the multiplication 
of cells in the solid point. Neither the cell material of the Wolffian 
duct nor the superficial epithelium or formative cells of the Wolffian 
body have any share. Dr. Wendeler traces the differentiation of the 
ducts to the end of foetal life, and describes the descensus o variorum 
and the origin of the coils. 
Development of Oculomotor and Trigeminal Nerves. f — Prof. G. 
Chiarugi has worked chiefly with embryos of the guinea-pig. He notes 
that in embryos of 3-3*6 mm. there are two primitive branches of the 
fifth — an ophthalmic and a mandibular, and that there is an intimate 
connection at this stage between the fifth nerve and the ectoderm. The 
latter is for a time in direct contact with the ganglion, but mesenchyme 
is eventually interposed. In embryos of 4*7 mm. a maxillary branch 
has been derived from the mandibular, and there is a distinct ophthalmic 
ganglion (not to be confused with the ciliary) which soon fuses with the 
ganglion of the fifth, forming a conical bud from whose apex the per- 
manent ophthalmic branch arises. No primitive connection between the 
third nerve and the ophthalmic of the fifth was observed. 
At a stage when the ophthalmic ganglion has fused with that of the 
trigeminal, and the ophthalmic branch has acquired a fibrillar structure, 
some ciliary filaments — proximal and distal — are seen arising from the 
ventral margin of the ophthalmic branch. 
The youngest embryos in which an oculomotor was seen measured 
4*5 mm. A rudimentary ganglion on the root of this nerve is distinct, 
and does not seem to be derivable from the passage of nerve elements 
from the fifth. Along the oculomotor, between the nerve fibrils, there 
are scattered nuclei, most difficult to interpret. These and the origin of 
the ciliary ganglion, the author discusses, but all so tersely that one 
would prefer to wait for his completed memoir. 
Theories of Dentition.^ — Dr. W. Kiikenthal agrees with Schwalbe’s 
general conclusion that the diphyodont condition of Mammals is inherited 
from Eeptilian ancestors, from the polyphyodont state. He argues 
against Leche’s view that there are in Mammals four sets of teeth, — 
(1) The oldest, quite functionless, only hinted at in the embryos of 
the lowest Mammals; (2) the second, or milk-set, functional; (3) the 
replacement-set, a new acquisition ; and (4) a fourth set of prospective 
importance. 
Kiikenthal reasserts his own conclusions: — (1) In all Mammals 
there are originally two sets, of which the second typically replaces 
the first. Both sets and the succession are inherited from ancestral 
forms. Hints of two other lost sets may be seen in embryos. (2) With 
increased specialisation the polyphyodont state has been replaced by a. 
* Arch. f. Mikr. Anat., xlv. (1895) pp. 167-99 (3 pis., 1 fig.), 
f Monitore Zool. Ital., v. (1891) pp. 275-80. 
i Anat. Anzeig., x. (1895) pp. 653-9. 
