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trabecula, which is not in accord with the position of the palatinus 

 trigemini in Bdellostoma. The hyomandibularis facialis is said to run 

 backward ventral to the otic process; and it accordingly lies morpho- 

 logically posterior to that process, and posterior also to the pedicle. 

 In determining the relations of these nerves to the several processes, 

 it is evident that Huxley considers the otic and ascending processes 

 as connected with the skull dorsal to the foramina of the nerves ; and 

 they are so shown in his Fig. 1, PL 1. 



In a 14 mm tadpole of Rana fusca, Gaupp (10) finds the quadrate 

 cartilage connected with the trabecula posteriorly by a processus 

 ascendens, and anteriorly by a commissura quadrato-cranialis anterior. 

 From the lateral edge of the cartilage a strong processus muscularis 

 projects upward and inward. In a 29 mm tadpole the quadrate is 

 further connected with the cranium ;by a processus oticus. Gaupp 

 says (p. 291) that the ascending process connects with the upper corner 

 of the trabecula. As the nervus trigeminus certainly issues from the 

 cranial cavity dorsal to the trabecula, the ascending process in Rana 

 must lie ventral to the nerve, and this is confirmed by Gaupp's state- 

 ment (p. 317) that the ganglion of the trigeminus "schiebt sich noch 

 sehr weit auf den Proc. ascendens hinauf nach vorne". Bearing these 

 conditions in mind, if Gaupp's figures 12 and 13 be consulted it will 

 be seen that the apparent relations of the trigemino-facialis nerves to 

 the process are as follows. The facialis passes downward through a 

 slit-like opening that has the appearance of being bounded anteriorly 

 by the ascending process, and posteriorly by the auditory capsule. 

 The ramus ophthalmicus (orbito-nasalis) trigemini passes downward 

 with the facialis through this opening, both nerves thus apparently 

 passing across the hind edge of the ascending process, and both 

 apparently having exactly the same relations to that process; that is, 

 both apparently lying posterior to it. The maxillo-mandibularis tri- 

 gemini runs forward across the dorsal surface of the process, and 

 thus apparently lies anterior to it. These apparent relations of the 

 nerves to the ascending process are thus exactly the reverse of what 

 Huxley gives for Menobranchus. Gaupp, however, himself says 

 (p. 446) that the maxillo-mandibularis always runs outward, posterior 

 to the ascending process. He must, accordingly, consider that to be 

 its relation to the process in Rana; but as the nerve actually runs 

 forward dorsal to the process, and as the process connects with the 

 skull ventral to the foramen of the nerve, the nerve can only lie 

 morphologically posterior to the process, under the assumption that 

 the position of the process, shown and described by Gaupp, is a 



