. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 60. In Scyllium stellare. -In this form, the olfactory cups and ol- factory bulbi are very large, as compared with the size of the brain. The sketch (Fig. 23), /f?-^'"^-^-^,^ was made from the brain of an adult specimen 78 cm long. The new nerve is relatively easy to dis- sect. Centrally, it is connected with the brain, on the ventral surface, a little in front of the middle point between optic chiasma and anterior margin of the prosencephalon. The lozenge-shaped ganglion (gn), lying close to the bulbus, is readily seen
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 60. In Scyllium stellare. -In this form, the olfactory cups and ol- factory bulbi are very large, as compared with the size of the brain. The sketch (Fig. 23), /f?-^'"^-^-^,^ was made from the brain of an adult specimen 78 cm long. The new nerve is relatively easy to dis- sect. Centrally, it is connected with the brain, on the ventral surface, a little in front of the middle point between optic chiasma and anterior margin of the prosencephalon. The lozenge-shaped ganglion (gn), lying close to the bulbus, is readily seen from above. Microscopic ex- amination of sections shows that the ganglion cells are larger than in Squalus (Fig. 2 A), but smaller than those of Alopias (Fig. 2 B). In front of the ganglion, the two principal branches of the nerve pass obhquely across the bulbus, as shown in the figure, to the fissure of the olfactory nerve. One branch joins the median, and the other the lateral division of the fila olfactoria. The chief stem subdivides and some of its smaller branches have been traced through the con- nective tissue covering of the olfactory cup into its interior. The new nerve has also been observed in Scyllium canicula and found to be very similar to that of S. stellare. In Pristiurus melanostomus. — The brain of Pristiurus is represented, natural size, in Fig. 24 A. At B, the same figure, the olfactory cup is shown with a ganglion at the base of the bulbus; at C, an outline diagram of the fore part of the brain as seen from below; and, at D, the ganglion with its two roots. The new nerve is connected with the ventral surface of the brain by two roots, as shown at C and D, Fig. 24. The roots are both slender and rather widely separated. The median one is larger than Fig. 23. Dorsal view of the braiuof an adnlt Scyllium stellare, nat. size. On the right the ganglion slightly Please note that these images are extracted from scanned page images that may have been d
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