DEVELOPMENT OF THE SACCUS ENDOLYMPHATICUS 237 
fe. 
ca.sc. Lat. 
Fig.2 Transverse section through the head of a larva. (Stage I.) Laby- 
rinth region. a, aorta br., gill; ch., chorda; d.e., ductus endolymphaticus; g.a., 
ganglion acusticum; h, heart; m, mouth; sac., sacculus; s.e., saccus endolymphat- 
icus; wir., utriculus; ven. 4, fourth ventricle. Figures 2-9 drawn by means of 
Edinger’s projecting apparatus. Leitz. obj. 3, oc. 3. 
Fig. 3 Transverse section through the head of alarva. (Stage II.) Laby- 
rinth region. c.t., connective tissue; ca., caleareous matter; f.e., foramen endo- 
lymphaticum; /, labyrinth; n.d.m., neural lamella of dura mater; p.d.m., periosteal 
lamella of dura mater; v.s., junction between neural and periosteal lamella of 
dura mater. 
