The brain of Acipenser. 257 
Plate 8 
Phots. 29, 30 and 31. Three consecutive sagittal sections through 
the commissura infima Halleri, section 31 being in the median plane. 
Fine fibres are traced to the commissure from the vagus lobe on the 
right. At the left are seen the coarse fibres of the more laterally 
situated spinal V tract. The few fibres seen in section 31 passing 
caudally from the commissure belong to the cervical bundle. X 60. 
Phot. 32. Lobus vagi. Cell of II type. X 120. 
Phot. 33. Lobus vagi. Cell with endings of IX fibres. X 137. 
Phot. 34 Valvula. Cell II type. X 120. 
Phot. 35. Valvula. Cell of “acusticum type” X 120. 
Phot. 36. Acusticum, cerebellar crest above. PurkınJe transitional 
and acusticum cells. Entrance of root fibres of VIII. X 120. 
Phot. 37. Acusticum, cerebellar crest above. PURKINJE cell. 
X 120. 
Phot. 38. Acusticum, cerebellar crest above. PurKinuE cells. X 120. 
Dorsal border turned toward the left on the plate. 
Phot. 39. Body of cerebellum. Cell II type with Purkinse 
dendrites. X 120. 
Phot. 40. Lateral lobes of cerebellum. Purkiny cells. X 60, 
Phot. 41. Lateral lobes of cerebellum. Purkınse cell. X 120. 
Patent 
Phots. 42, 43 and 44. Three examples of Purkınsp cells with 
varicose or moniliform dendrites, from cephalic part of valvula 
De 120. 
Phot. 45. Acusticum, cerebellar crest above. PurkınsE cells. 
x 83. 
Phot. 46. Base of mid brain. Part of decussation of fine fibres of 
the bundles of Mevyxerr, together with a few fibres belonging to the 
commissura ansiformis. X 83. 
Phot. 47. Tectum. To the right, a cell of the torus longitudinalis 
showing neurite entering middle fibre zone. To the left, a cell of type 
aor. x 120. 
Phot. 48. Tectum. Cell of torus longitudinalis. X 120. 
Phot. 49. Tectum. Cell of type D, middle zone. X 120. 
Phot. 50. Tectum. Cell of Il type (type A of text). Branching 
of short neurite outside of fibre zone. Cell body not present. X 120. 
Phot. 51. Tectum. Cell of II type (type A). Simpler branching 
of the neurite in outer part of middle fibre zone. X 120. 
Phot. 52. Tectum. Cell of type D. X 120. 
Phot. 53. Tectum. Cell of type B. X 120. 
Zool. Jahrb. XV. Abth. f. Morph. 117 
