250 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Explanation of Plates. 
All drawings were made with the aid of the camera lucida. 
The magnification for Plate 1 was obtained with a Leitz dissecting micro- 
scope; for Plate 2, a Reichert objective No. 3 and ocular No. 4 were used; and 
for Plates 3, 4, 5, and 6, a Reichert ais inch homogeneous immersion objective 
and ocular No. 4. 
ABBREVIATIONS. 
amp. a. Ampulla anterior. 
amp. hz. Ampulla horizontalis. 
amp. p. Ampulla posterior. 
apxr. Sn. SU. . Apex sinus superioris. 
can. a. Canalis anterior. 
can. hz. . Canalis horizontalis. 
can. p. Canalis posterior. 
CT. QC. Crista acustica. 
ie ae ae Lagena. 
mac. lgn. . Macula acustica lagenae. 
mac. ngl. Macula neglecta. 
mac. rec. utl. 
Macula acustica ree. utriculi. 
mac. sacl. . Macula acustica sacculi. 
nm. oct. Nervus octavus. 
rec. ull. . Recessus utriculi. 
rm. a. Ramus anterior. 
rml. amp. a. . 
rml. amp. hz. . 
rml. amp. p. . 
~Ramulus amp. anterioris. 
Ramulus amp. horizontalis. 
Ramulus amp. posterioris. 
rml. lgn. Ramulus | genae. 
rm. p. Ramus posterior. 
Saerx 5. Sacculus. 
sn. ull. su. Sinus utriculi superioris. 
utl. Utriculus. 
