NOsga)) JIOSCLES AND NERVES, INVAMIA CAEVA. 605 
so on the right, as indicated by the projecting nerve end in the 
figure (4/2012, Fig. 19, Pl. XXIII). 
The branches to organs 10 to 7 infraorbital, inclusive, arose 
successively from the buccalis at fairly equal distances apart. 
The branches to organs 6 and 5 arose close together, that to 
organ 6 passing outward above, that is, behind and lateral to the 
fourth division of the levator maxillae superioris as in 40 mm. 
specimens, but that to organ 5 passing through that muscle at 
its origin instead of under it, that is, in front of it, as in the 
young. The buccalis itself also passed through this fourth 
division of the muscle instead of between it and the third divi- 
sion asinthe young. Beyond this point the branches to organs 
4, 3, 2, and 1 were given off regularly in succession, the nerve 
ending in the last-named organ. 
da. Truncus Maxillaris Trigemini. 
The truncus maxillaris separates immediately, in the adult, 
into its two main portions, the r. maxillaris superior (#s¢) and 
the r. maxillaris inferior (#zt). From these two nerves close 
to their origin, from the truncus maxillaris itself, from the 
upper surface of the main trigemino-facial ganglion, and perhaps 
also in part from the r. ophthalmicus superficialis, several small 
nerves arise. They vary in number and arrangement in every 
specimen and are the homologues of the three accessory tri- 
geminal branches described by Strong in Rana (No. 121, p. 
111). In the specimen used for illustration one of these 
nerves issued from the cranium with the ophthalmic nerves 
through the ophthalmic foramen ; the others all issued with the 
superior and inferior maxillary nerves through the main tri- 
geminal foramen. They formed numerous anastomoses with 
each other and were distributed almost entirely to the fatty 
and other tissues above and behind the eye and to the dermal 
and subdermal tissues of the cheek. On the left side of the 
head there were five of these nerves, a, 6, c,d, ande. They 
are shown much enlarged in Figs. 38 and 39, Pl. XXX. In 
these figures the nerves are all pulled somewhat apart and 
hence somewhat displaced from their natural positions, and in 
