— 44 — 



minus, lateralis trigemini and ciliaris profundi nerves from its anterior opening. The Chamber lodges 

 the trigeminus portion only of the trigemino-facialis ganglionic complex, together with the associated 

 sympathetic ganglia, a recess on the cerebral surface of the bone lodging the lateralis and communis 

 portions of the ganglionic complex. The chamber might accordingly be more properly called the 

 trigeminus or semilunar Chamber, the recess on the cerebral surface of the bone being called the 

 facialis or geniculate recess. But until the manner of development is better known, of this chamber 

 and recess, from a single chamber lodging the entire ganglionic complex, as in Amia, it seems to me 

 best to retain the name already given to the chamber in Scomber, and to call the recess the tri- 

 gemino-facialis recess. The main sympathetic trunk, the jugular vein, the external carotid artery 

 and the vessel x all traverse the chamber in Scorpaena, the chamber thus representing either 

 the whole or a portion of the upper lateral chamber of the eye-muscle canal of Amia (Allis, '03, p. 94). 

 Into the chamber two to four foramina open; a large trigeminus one, a slightly smaller facialis one, 

 and two small foramina, one or both of which may be included in the large trigeminus foramen. One 

 of the two small foramina, when found, transmits the ramus ophthalmicus lateralis, the other trans- 

 mitting the truncus ciliaris profundi. The ophthalmicus foramen lies slightly dorso-anterior to 

 the trigeminus foramen, this latter foramen lying anterior to the facialis foramen, while the pro- 

 fundus foramen lies in the internal jugular groove at a variable distance anterior to the trigeminus 

 foramen. The trigeminus foramen transmits the radix trigemini, the ramus buccalis plus oticus 

 lateralis and the encephalic brauch of the jugular vein. The oculomotorius traverses a foramen that 

 perforates the proötic anterior to these several foramina, as will be later described, and in one 

 instance this nerve was accompanied, as it traversed its foramen, by the truncus ciliaris profundi. 

 Sagemehl says ('91, p. 568) that in the Cyprinidae the ramus ophthalmicus superficialis (trige- 

 minus lateralis) always perforates the alisphenoid; and Stannius says ('49, pp. 33 & 36) that this 

 same nerve pierces the alisphenoid (Keilbeinflügel) in most teleosts. Sagemehl further says ('84b, 

 p. 70) that independent foramina for the truncus trigemini and the ramus ophthalmicus superficialis 

 trigemini is a primitive condition, and that a single foramen for these two nerves is exceptional. 

 Neither of these Statements is true either for Scomber or Scorpaena, and it would seem as if the 

 foramina referred to must be, as in Amia, the foramina by which the nerves referred to issue from a 

 trigemino-facialis chamber and not those by which they issue from the cranial cavity to enter that 

 chamber. That there is a radical difference in these two sets of foramina was pointed out in my 

 work on Scomber, and will be further discussed in the course of the present work. 



The ventral portion of the proötic of Scorpaena, the part that lies ventral to the mesial process 

 of the bone, forms, as usual, the lateral wall of the myodome, and its ventral edge is edged its füll 

 length with a broad band of cartilage, this cartilage being held in a deep slit-like groove in the edge 

 of the bone. This groove lies between thin external and internal laminae of the proötic, of perichon- 

 drial origin, the anterior edges of these laminae being united along the anterior edge of the bone. 

 The anterior edge of the endosteal bone, thus formed, then receives membranous additions which 

 prolong it anteriorly, especially in its dorsal portion. Ventro-mesial to this edge of the bone, the 

 ventro-anterior corner of the edging band of cartilage is cut away to form a large incisure which 

 bounds the passage for the internal carotid artery. Posterior to this incisure the ventral edge of the 

 edging cartilage forms the lateral boundary of the hypophysial fenestra, the ventral edge of the 

 cartilage being presented ventro-mesially and abutting against the lateral surface of the median 

 ridge on the dorsal surface of the postorbital portion of the parasphenoid. 



