DAVENPORT: PROCESSES CONCERNED IN. ONTOGENY. 179 
penetrate between the blastomeres, so that it is difficult to tell which 
part of the embryo has been derived from the egg and which part by 
immigration. Compare the 
origin of the cutis in Echino- 
derms (K. & IL, Fig. 195), in 
Mollusca (K. & H., Fig. 686), ~ 
di 
and in Vertebrates (M., Fig. Y 
306), and of the intestinal and 
vascular musculature of Verte- Stolen on 
brates (H.-M., Fig. 185). ventral side. 
All of these processes have 
this in common, that mesen- 
chyme migrates to an organ 
— vessel, layer, or mass — and 
applies itself closely to it, 
base, sre 
sometimes even penetrating , 
trans/e, 
into the substance of the 
organ. 
6. Transportation by Mes- 
enchyme has hitherto been 
observed in but few cases. 
The most remarkable instance 
of this process is found in the 
Doliolidee, where the buds pro- 
duced from a stolon are trans- 
ported over half the length 
and half the circumference of 
the body by means of mesen- 
chyme cells, and are finally 
deposited, in very regular or- 
der, on the appendage of the 
Dorani sto len. 
budding individual. (Figures 
and í )v similar means 
8 and 9.) Dy similar means, Fie. 8. 
apparently, one end of the 
funiculus of the Bryozoan Cristatella is transported from the dorsal to 
the ventral surface of the corm, as I have attempted to show elsewhere. 
(Bull. Mus. Comp. Zodl., XX. 142.) 
“nurse.” Shows 
Fig. 8. Dorsal view of the posterior part of a large Doliolum 
the buds being transported from the ventral to the dorsal (and posterior) stolon. 
(See K. & H., Fig. 830.) 
