786 KEPORT — 1892. 



4. (a) The ganglionic enlargement in the pre-somitic region becomes converted 

 into the root ganglia of the glosso-pharyngeal and vagus nerves. 



(p) The ganglionic enlargement in relation with the fourth somite becomes 

 the tirst cervical ganglion. 



(c) In the rat and tlie mouse the ganglionic enlargements in relation with the 

 second and third somites become connected with the spinal accessory nerve, but 

 in the cat the enlargement in relation with the third somite becomes united with 

 the most posterior root of the hypo-glo.ssal nerve. 



5. After the separation of the cellular cord from the dorsum of the neural tube 

 a series of nerve roots are developed, and by means of these the cellular cord and 

 its ganglionic swellings become secondarily connected with the neural tube in the 

 region of the angle between the alar and basal laminse. 



6. The nerve roots are divisible into two series : — 



(a) A dorsal series, which pass partly into the cellular portion of the neural 

 tube and partly into the white columns in the region of the ascending roots of the 

 vao-us and glosso-pharyngeal nerves. These roots are from twelve to fifteen in 

 number, and in the region of the spinal accessory nerve they appear to terminate 

 almost entirely in the cellular wall of the neural tube dorsal to the next series of 

 roots. 



(6) A lateral series, which leave the neural tube either together with, or a short 

 distance ventral to, the dorsal series. Many of these roots pass beneath the 

 ganglionic chain, but others appear to be connected either with the ganglia or the 

 cellular strand which unites them. Centrally these roots are connected with the 

 dorsal angle of a column of cells situated along the ventro-lateral aspect of the 

 neural tube, which ultimately becomes the anterior grey cornu and its cephalic 

 continuation. Peripherally they pass, in the region of the second and third 

 somites, into the spinal accessory nerve, and further forward into the stems of the 

 "■losso-pharyngeal and vagus nerves. In the region situated between the fourth 

 and eighth "somites they pass directly into the spinal accessory nerve, and have no 

 connection with the ganglia of the cervical nerves. 



7. The cellular commissure, which in the early stages can be traced backwards 

 beyond the cervical region, terminates in the later stages as a continuous cord, at 

 the second cervical ganglion, but traces of it can be found much further back- 

 wards. 



8. The dorsal roots of the cervical ganglia enter the cord on the same level as 

 the dorsal roots of the accessory and vagus nerves, and terminate, like the dorsal 

 roots of the vagus, partly in the white columns and partly in the cells which are 

 afterwards situated at the region of the base of the posterior grey horns. 



0. The hypo-glossal roots spring from the ventro-lateral angle of the neural 

 tube, taking origin from the column of cells which in the cervical and post-cervical 

 regions becomes converted into the anterior grey cornu. 



The most anterior rootlets are collected into a small bundle which lies in front 

 of the first somite. The remaining rootlets are gathered into three bundles, one 

 of which lies in relation with the ventral portion of each of the three first somites, 

 and below the level of the somites all four bundles are collected into one trunk. 



4. On Cranial Ganglia. Bij Professor J. CossAR Ewart, M.D., F.B.S.E. 



5. Renewed Experiments on the Modification of the Colours of Lepidopteroics 

 Pvpce. By E. B, Poulton, F.B.S. 



6. An Olservation hearing on the Non-transmission of Characters required 

 by certain Pupce. By E. B. Poulton, F.B.S. 



