424 * 
PALAEONTOLOGY OF NEW-YORK. 
SUPPLEMENTARY NOTE ON THE GENUS PTERYGOTUS. 
The monograph of Messrs. Huxley and Salter, referred to on page 417 # , 
furnishes the accompanying illustration of the Genus Pterygotus ; being 
a restored diagram of P. bilobus, of the natural size. 
The figures and letters, with the reference to the parts, and the no¬ 
menclature employed, are copied from the explanations of the figure in 
that monograph. 
t 
a. Eyes. 
b. Antennse. 
b'. Chela. 
c. The endognaths with 
their palps : their ba¬ 
sal joints are, for dis¬ 
tinctness’ sake, repre¬ 
sented as if they were 
widely separated in 
the middle line. 
d. e. The ectognaths, 
with their palps. 
/. The epistoma, or con¬ 
joined epistoma and 
labrum. 
g. The metastoma. 
1 - 13. Successive seg¬ 
ments : 1, carapace; 
2 -12, segments of the 
body; 13, telson. 
