498 SLONAKER. 



EXPLANATION OF PLATE XXIX. 



Fig. 40. Tern (Sterna hirundo). Vertical section across band-like area {a) on 

 the nasalis side of the fovea nasalis. Section 36/u thick. X 32.3. 



Fig. 41. Tern (Sterna hirundo). Horizontal section through center of fovea 

 nasalis. Section 30/U thick. X 32.3. 



Fig. 42. Tern (Sterna hirundo). Vertical section across band-like area (a) 

 about midway between fovea nasahs and temporalis. Section 36;U thick. X 32.3. 



Fig. 43. Tern (Sterna hirundo). Horizontal section through center of fovea 

 temporalis. Section 30/i thick. X 32.3. 



Fig. 44. Kingfisher (Ceryle alcyon). Horizontal section through center of 

 fovea nasalis. Section 30/i thick. X 32.3. 



Fig. 45. Kingfisher (Ceryle alcyon). Horizontal section through center of 

 fovea temporalis. Section 30/i thick. 32.3. 



Fig. 46. White-Bellied Swallow (Tachycineta bicolor). IJorizontal section 

 through center of fovea nasalis. Section 24/i thick. X 32.3. 



Fig. 47. Ring-Neck Plover (.lEgialitis semipalmata). Horizontal section 

 through fovea of left eye. Section iS/i thick. X 32.3. 



Figs. 48, 49. Sparrow Hawk (Falco sparverius). Section passed through 

 each fovea and center of pupil. Fig. 48, fovea nasalis and Fig. 49, fovea tempo- 

 ralis. Section 42(U. thick. X 32.3. 



Figs. 50, 51. Red-Tailed Buzzard (Buteo borealis). Section passed in plane 

 of both foveae and center of pupil. Fig. 50, fovea nasalis and Fig. 51, fovea 

 temporalis. Section 42/Lc thick. X 32.3. 



Fig. 52. Crow (Corvus americanus). Horizontal section through center of 

 fovea. Section 36/x thick. X 32.3. 



Fig. 53. Blue Jay (Cyanocitta cristata). Horizontal section through center 

 of the fovea. Section 48/i thick. X 32.3. 



Fig. 54. Shorepeep (Ereunetes pusUlus). Horizontal section through center 

 of fovea of left eye. Shows some cells of the area lying beyond the center of the 

 fovea. Section 24^11 thick. X 32.3. 



Fig. 55. Barred Owl (Symium nebulosum). Horizontal section of right eye 

 through center of fovea (fovea temporalis). Section 48/i thick. X 32.3. 



