Terry — The Nasal Skeleton of Ambly stoma imnctatum. 1 07 



rimal duct by the Lamina cribrosa. The uasohicrimal duct 

 crosses this little bridge to end in the nasal sac. Followed in 

 the opposite direction, the duct runs back in a slight groove 

 on the side of the nasal capsule (original Lamina cribrosa). 

 A little elongate (in section) mass of densely packed cells is 

 applied to the medial side of the bridge near the trabecular 

 horn. I suspect that this is the anlage of the dilator naris 

 muscle. 



The cartilaginous nasal capsules of the 69mm. Ambly- 

 stoma described by Winslow ('98) present conditions which 

 are, in the main, probably the results of continued growth and 

 readjustment of the parts present in the stage just described. 

 The capsules are mostly anterior to the brain-case and the 

 olfactory foramina look forward and a little outward. 

 There is no longer a medial incisure, only a small foramen 

 (Fig. 12, ni.), the Foramen apicale (Gaupp '05.1), transmit- 

 ting a branch of the Nasalis internus. The Lamina and 

 antorbital process are united in a posterior wall or cupola, a 

 foramen (orbito-nasal) being enclosed. Three windows are 

 shown (fig. 12) in the capsular wall. The largest is situated 

 dorsally and is separated by a strip of cartilage called " dor- 

 sal process " from the other two foramina. These openings 

 are placed laterally, separated from each other by a *' short 

 connecting rod." The hinder of the two is at about the 

 middle of the capsule in its cephalo-caudal extent. In the 

 explanation of the figures (p. 199) " nl.", which points to 

 this foramen, refers to ** nostril;" and in the text (p. 159) 

 the short connecting rod (the anterior boundary of the for- 

 amen) is said to be in front of the nasal duct. 



In the nasal capsule of the adult studied by means of fron- 

 tal sections I find these windows. Jacobson's organ appears 

 in the posterior of the lateral openings, the Fenestra infra- 

 conchalis (Gaupp, '05.1) while the external naris and the 

 termination of the nasolacrimal duct were found in the 

 anterior one, the Fenestra narina. 



The nerves were reconstructed in my stage IV in order to 

 to observe their relations to the nasal skeleton ; the refer- 



