Bull. U. S. F. C. 1895. The American Lobster. (To face page 209.) 
Plate I. 
Cut 31. — Surface view of egg nauplius, 
showing thoracic abdominal fold. The 
mouth, as in cut 30, is screened by the lab 
rum, and the optic disks are more sharply 
defined; second antenna? forked; embryo 
about 12 days old. 29 diameters. 
Cut 33.— Surface view of embryo with first 
maxillae budded ; embryo 16 to 18 days 
old. August 5. 29 diameters. 
Iu cuts 31-38 there is little attempt to 
show more than the form of the embryo. 
The series G to J represents the progres- 
sive development of the summer eggs. 
Compare the Rate of Development, pp. 
55 to 57, and table 18. 
Cut 32. — Surface view of egg nauplius, 
showing parts much more concentrated 
than in earlier stages. Antenna? exhibit 
traces of segmentation, and the second 
antenna? have a slender inner branch. 
The abdomen is bifid at its extremity, 
which nearly touches the labrurn ; optic 
disk lobular; embryo 14 to 16 days old. 
August 14. 29 diameters. 
Cut 34. — Surface view of embryo, showing 
5 pairs of post-mandibular appendages. 
The antennae have grown obliquely back- 
ward until they come to lie nearly paral- 
lel with the abdomen. The telson, which 
is now distinctly forked, partially over- 
laps the brain. Eye-pigment not yet 
apparent. Nearly same stage as 3 (5), 
table 18; about 21 days old. From egg 
killed in Perenyi fluid, August 15, 1893. 
29 diameters. 
Drawn l)\j F. H. Herrick. 
