Bull. U. S. F. C. 1 895. The American Lobster. (To face page 86.) 
Plate B. 
Cut G. — Left clieliped of lobster seen from the dorsal side. From specimen which molted in an aquarium 
July 13, 1891, and which is described in Chapter III, pp. 83 to 85. See No. 7, table 24. One-half nat- 
ural size. 
The Roman numerals I-IY correspond to the planes of section illustrated in cut 7; A rabic num- 
erals 1-7 to segments of limb, mb, area of absorption, on upper surface of third and fourth joints. 
x , plane of fracture. 
Cut 7. — I-IY represent transverse sections of clieliped shown in cut G in the planes indi- 
cated by corresponding numerals, II and IV showing the natural openings at the proximal 
ends of the sixth and first segments respectively. Ia-I Va represent the areas of the 
respective sections expressed graphically and numerically. (The plotted areas are 
two-thirds natural size; the numerical expressions above them refer to actual areas.) 
At mb, cuts 6 and 7 (III), the lime salts of the shell have been absorbed, so that the 
cuticle is capable of distention, and the area of the transverse section is thereby 
slightly increased. The muscles and other tissues which fill the transverse section la 
must be drawn through an openiug the size of I la, then through one but little larger 
than Ilia (allowing for the distention of the membrane), and finally through the small 
ring, IY. IVa , at the base of the limb, since there is no rupture of any of these parts. 
Drawings two-thirds natural size. 
1 
Drauni htj F. FI. Herrick. 
