(396) H. N. Moseley. “On the Structure and Development of Peripatus capensis.” Phil. Trans. Vol. 164, 1874.
Myriapoda[163].
Chilognatha. The first stages in the development of the Chilognatha have been investigated by Metschnikoff and Stecker, but their accounts are so contradictory as hardly to admit of reconciliation.
According to Metschnikoff, by whom the following four species have been investigated, viz., Strongylosoma Guerinii, Polydesmus complanatus, Polyxenus lagurus, and Julus Moneletei, the segmentation is at first regular and complete, but, when the segments are still fairly large, the regular segmentation is supplemented by the appearance of a number of small cells at various points on the surface, which in time give rise to a continuous blastoderm.
The blastoderm becomes thickened on the ventral surface, and so forms a ventral plate[164].
Fig. 173. Three stages in the development of Strongylosoma Guerinii.
(After Metschnikoff.)
A. Embryo on eleventh day with commencing ventral flexure (x)
B. Embryo with three pairs of post-oral appendages.
C. Embryo with five pairs of post-oral appendages.