122 WILLIAM BATESON. 
Fie. 59.—A diagram of a transverse section taken through the anterior 
region of the collar, to show the relation of the parts figured in Fig. 60. 
(Obj. A, oc. 2.) 
Fic. 60.—The dorsal structures of the anterior part of the collar shown in 
Fig. 59, viz. the nervous system, notochord, perihzmal cavities, &c. (The gut 
is torn away from the skeletal rod, presumably by shrinking.) The lateral rods 
are here connected to the notochordal sheath. (Obj. D, oc. 2.) 
Figs. 61—63 show transverse sections of parts of B. minutus. 
Fic. 61.—The notochord in transverse section in front of its lumen. (Obj. 
CC, oc. 2.) 
Fic. 62.—The same in the region of the proboscis stalk. 
Fic. 63.—Through the notochord, &., in the front of the collar, showing 
the thickened dorsal half of the organ. (Obj. CC, oc. 2.) 
ERRATUM. 
In the body of the preceding paper (not in the Description of the Plates), 
for Fig. 45, read Fig. 44, and for Fig. 46, read Fig. 45. 
