( 1048 ) 
two reptiles, Alligator sclerops and Chelone midas: 
one bird, Ciconia alba; 
and several mammals, viz. : 
two Marsupials: Macropus robustus and Didelphys; 
two Rodents: Cavia cobaya and Lepus cuniculus; 
one Ungulate: Equus caballus 
and one cetacean: Phocaena communis. 
Raja. 
In viewing a series of frontal sections through the oblongata of 
Raja, one observes everywhere the large reticular cells arranged fairly 
uniformly along the lateral and ventro-lateral border of the fasciculus 
longitudinalis posterior. Only in the caudal part of the oblongata, 
on the level of the extrance of the Xt roots, is a different form to 
be found owing to the reticular cells here being greatly massed in 
the raphe. 
The reticular cells of the bulb of Raja form one continuous series. 
They are not, however, distributed equally over the bulb; on some 
levels they are to be found more massed, so that one might speak 
of reticular nuclei. The reticular cells in Raja ean be divided — on 
descriptive anatomical grounds —- into 3 groups, viz.: 1s", a caudal 
group, occurring on the level of the extrance of the X roots, Dad | 
a group occurring on the level of the entrance of the VIII roots, 
and a 3'¢ group, which comprises the series of reticular cells front- 
ally from the VIII’s entrance. For the sake of convenience these may 
be termed nucleus reticularis inferior, medius, and superior. 
Fig. 1 represents a more caudal level, Fig. 2 a more frontal level 
of the X roots. The accumulation of cells between the fase. longit. 
post. and the base can be seen, with a marked raphe nucleus (figs. 
1 and 2:a.) and wings which stretch out sideways, wreath-like, 
underneath and along the border of the fase. long. post. Some of 
these cells lie fairly dorsally, lateral from the fase. long. post. (Figs. 
1 and 2:4). Other cells lie more ventrally in the formatio reticu- 
laris. (Figs. 1 and 2:c). A few smaller reticular cells lie rather 
far laterally. (Figs. 1 and 2:/). The reticular nucleus of the X 
region can be detined caudally as well as frontally. In the caudal 
direction the number of cells gradually decreases both in the raphe 
and in the formatio reticularis, while the cell-type also grows 
smaller. Frontally from the entrance of the X roots the number of 
reticular cells likewise decreases, so that between the and VIII 
root-entrances a region occurs, where but few reticular cells are 
found. On the level of the entrance of the octavus another massing 
