. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 22 bulletin: museum of comparative zoology of the pars quadrata and apparently representing the r. hyoideus, (3) and (4) two dorsally directed branchlets passing to the muscles of that region. The two small branches referred to above as becoming as- sociated with the V. capitis lateralis, maintain a ventral position with respect to the latter, but eventually fuse, in the region of the anterior margin of the operculum, dorsal to which they lie and. are then joined by one coming from the angle of the buccal cavity. I ha
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 22 bulletin: museum of comparative zoology of the pars quadrata and apparently representing the r. hyoideus, (3) and (4) two dorsally directed branchlets passing to the muscles of that region. The two small branches referred to above as becoming as- sociated with the V. capitis lateralis, maintain a ventral position with respect to the latter, but eventually fuse, in the region of the anterior margin of the operculum, dorsal to which they lie and. are then joined by one coming from the angle of the buccal cavity. I have traced this latter nerve forwards very carefully, and find that, at about the region of the optic foramen it splits into two branches lying in the lateral portion of the tongue and separated from the main lingual stem of No. IX by a short space occupied by two arteries. Somewhat farther forward, first the inner branchlet, then the outer fuses with the main stem of No. IX, and the composite nerve then innervates the tongue. The ramifications of No. VII and No. IX are given very schemati- cally in Fig. 8, in w^hich the two rami of No. VII associated wuth the vena capitis lateralis are designated as p 1 and p 2, and the product of their fusion p. The nerve which is very closely associated with p, and. Fig. 8. Schematic representation of the ramifications of the seventh and ninth cranial nerves in Ascaphus. glph = nervus glossopharyngeus; lgbg = lingual branch of glossopharyngeus; nac = nervus acusticus; ntr = nervus trigeminus; p, p 1, p 2 and q are explained in the text. Other abbreviations as for previous figures. fuses with No. IX in the tongue, is labelled q. The p and q elements are practically fused in Fig. 9C although their boundaries can still be made out; in Fig. 9A and B they are merely opposed. Fig. 9B marks the shifting of No. IX to lie dorsal to p + q, and already No. X is beginning to appear. In Fig. 9C the roots of nerves IX and X to- gether with p + q may be see
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Keywords: ., bookauthorharvarduniversity, bookcentury1900, booksubjectzoology
