220 RITTER. [Vou. XII. 
D. SUMMARY OF RESULTS. 
GOODSIRIA DURA. 
1. The budding is pallial, and the buds arise far forward on 
the parent zooid. In no case has more than one bud been 
seen on the same parent. 
2. No “budding zone” is recognizable in zooids on which 
buds are not developing. 
3. The buds become wholly separated from the parent 
zooids at a very early stage, z.e. before any differentiation of 
organs begins; and at a considerably later time they become 
secondarily connected with the vessels of the test. 
4. The ampullae of the testicular vessels do not produce 
buds. 
5. The formation of the branchial and peribranchial sacs, 
and of the digestive tract from the primitive inner, or endo- 
dermic, vesicle of the bud does not differ in any essential 
particular from that of all other Compound Ascidians. 
6. The common Ax/age of the pericardium and heart is de- 
rived from the wallof the endodermic vesicle by an imperfect 
evagination that does not become fully separated until the 
ventral partitioning folds which separate the peribranchial sacs 
from the branchial sac have reached back to the region where 
the heart is forming. 
7. The ganglio-hypophyseal Ax/age arises as a gutter-shaped | 
evagination from the dorsal side of the endodermic vesicle. As 
this closes off to become the hypophyseal duct, the ganglion is 
produced from the mass of cells that forms the last of the con- 
nection of the duct to the endodermic vesicle. The ganglion, 
therefore, in this species as in Botryllus, lies ventral to the 
hypophyseal duct. 
8. The youngest sexual cells observed were found free in 
the body space of the buds, so that in all probability they pass 
from parent to bud as is the case in Botryllus. But in none 
of the material available for study were the elements present 
in sufficient quantity and development to make it possible to 
give a complete history of them. The ‘polycarps”’ appear to 
