Bull. U S. F. C. 1895. The American Lobster. (To face page 208.) 
Cut 27. — Surface view of embryo, show- 
ing buds of first pair of antennae and 
clouds of in-wandering cells. Tbe lat- 
ter extend in great cumulus-like folds 
and surround large masses of yolk with 
thin layers of cells. Embryo about 9 
days old. August 6, 1891. 29 diameters. 
In cuts 25-33 the eggs were fixed with 
hot water and Mayer’s picro-sulphuric 
acid, and stained in Kleinenberg’s hmrno- 
toxylon or Grenacher’s borax -carmine. 
Cut 29. — Surface view of early egg- 
nauplius embryo, showing buds of 
the first and second antennae and 
the mandibles. Mouth or opening 
of stomodaeum distinct; in-wandering 
cells beneath the thoracic abdominal 
plate shaded dark. The yolk-cells are 
still further circumscribed to outward 
appearance, having wandered far into 
the egg. Optic disks more clearly de- 
fined. Embryo about 10 days old. 29 
diameters. 
Plate H. 
Cut 28. — Surface view of embryo, show- 
ing buds of first pair of antennae and 
of mandibles. The stomodaeum is 
present in form of a small transverse 
pit, on the level of a line drawn 
through the posterior margins of the 
antennary buds. The outlines of the 
masses of yolk-cells appear much 
more circumscribed than in the earlier 
stage shown in cut 27. Embryo 9 to 
10 days old. August 5, 1891. 29 dia- 
meters. 
Cut 30. — Surface view of egg nauplius, 
slightly older than that shown in cut 29; 
second antennae bifid ; labrum and tho- 
racic abdominal fold present; embryo 
about 11 days old. July 12. 29 diame- 
ters. 
In cuts 25-30 surface-cells are roughly 
indicated only in the immediate region 
of the embryo. 
Drawn by F. H. Herrick. 
