72 GLOSSARY. 



Lamel'la (L. a thin plate). A thin layer or plate. Applied to 

 the thin plates in the hymenitim of a mushroom; also to 

 the gills of the Lamellibranchiata. 



Lamellibranchia'ta (L. lamella, a thin plate; Gr. branchia, a 

 gill). A class of the Mollusca in which the gills are com- 

 posed of plate-like folds of membrane. 



La'mina (L. a thin plate). A thin layer. 



La'mina cine'rea (L. ashy layer). A thin layer of grey nerve 

 tissue between the optic commissure and the corpus cal- 

 losum of the brain. 



La'mina cribro'sa (L. sieve-like layer). The perforated region of 

 the sclerotic where the optic nerve enters. 



La'mina elastic (L. lamina, a thin plate). A layer of the 

 corner of the eye, immediately beneath the anterior epi- 

 thelium. 



La'mina fus'ca (L. dark layer). A delicate layer of connective 

 tissue on the inner surface of the sclerotic. 



La'mina reti'cular (L. lamina, a thin plate ; retiatlum, a little 

 net). A delicate network of epithelial cells covering a 

 part of the organ of Corti. 



La'mina spira'lis (L. spiral plate). The dividing bony septum of 

 the cochlea of the ear. 



La'mina suprachoroi'dea (L. the plate above the choroid). A 

 delicate membranous layer bounding externally the cho- 

 roid coat of the eye. 



La'mina termina'lis (L. terminal plate). The layer which 

 bounds anteriorly the third ventricle of the brain. 



La'minae dorsa'les (L. dorsal plates). The folds of the vertebrate 

 embryo which rise up by the sides of the primitive groove, 

 and close it in to form the future neural canal. 



La'minae viscera'les (L. visceral plates). The folds of the blasto- 

 derm from which are developed the ventral body-walls 

 and their contained organs. 



Lan'guet (Fr. a tongue-shaped body). A term applied to the 

 tentacles of the Tunicata. 



Lanu'go (L. wool or down). The first crop of hairs or down on 

 the skin. 



Laryn'goscope (Gr. lammx, the windpipe ; skopeo, I behold"*. 

 An optical instrument by which the throat and larynx 

 may be brought into view. 



Laryn'go-trache'aL The name given to the annular cartilage 

 in the frog, to which the arytenoid cartilages are articu- 

 lated. 



