EXPLANATION OF PLATE 10 
Fig. 1. Cross-section of the myelencephalon and myelencephalic gland 
of a Lepisosteus osseus, 250 mm. in length. Section taken slightly cepha- 
lad of middle of gland, and cut farther cephalad on right than on left. 
< 12. 
ABBREVIATIONS 
A—region where tissue of gland extends into pia mater. 
éth vent.—fourth ventricle. 
bl. ves.—hblood vessel. 
col. e.—columnar epithelial cells. 
conn. tiss. n.—connective tissue network. 
d. gran. M.—region dense with granular masses. 
endol.—endolymph. 
/l. e.—flattened epithelial cells. 
inf. pl—infolding of choroid plexus. 
med.—medulla oblongata. 
nerv.—nerve. 
pig.—pigment cell. 
p. m.—pia mater. 
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