SCHULTE, SEI WHALE. 433 



the choanse. Caudad it diminishes more gradually as far as the thyroid cartilage, but opposite 

 to it it abruptly narrows to join the oesophagus. The maintenance of its transverse diameter 

 in the region of the laryngeal junction stands in relation to the great breadth of the trachea. 

 The interior of the pharynx is profoundly modified as a consequence of the retrovelar position 

 of the epiglottis and the concomitant lengthening of the fauces to a tubular passage, the bucco- 

 pharyngeal canal of Turner. This latter depends for its formation upon a lengthening of the 

 velum palati, which projects far caudad into the cavity of the pharynx terminating as a crescentic 

 fold, the horns of which prolonged upon the sides of the pharynx are the arcus palatopharyngei. 

 In the Odontoceti these are prolonged upon the dorsal wall of the pharynx forming a muscular 

 annulus palato-pharyngeus (Ruckert). In this fetus the annulus is not circular, but rather 

 pyriform with the wide end rostrad. Caudad the narrow part of the annulus is formed by a 

 thick muscular ridge of the dorsal wall, prolonged upon the sides by fairly well defined ridges, 

 which can be followed to the back of the hyoid beside the epiglottis. They owe their promi- 

 nence chiefly to deep sulci at their caudo-ventral margins, which separate them from the larynx 

 which between them rises into the pharynx. The position of this ridge would suggest that its 

 muscular basis is a specialization of the middle constrictor, rather than an extension of the 

 palatopharyngeus. The annulus in this foetus is therefore composed of two crescentic ridges, 

 with their cornua approximated but not actually continuous, nor even in line with one another. 

 The dorso-caudal crescent embraces the arytenoids, the ventro-rostral corresponds to the epi- 

 glottis but abutts closely upon it only in front and on the left side. A low oblique ridge extends 

 from the velum to join the horn of the dorso-caudal crescent opposite the interval between 

 arytenoid and epiglottis. Their junction is marked by a small triangular elevation. This ridge 

 defines the region of the faucial orifice, in which is also contained the base of the epiglottis. The 

 position of the larynx is already asymmetrical and a rod passed into the fauces here emerges 

 to the right of the epiglottis. Dorsal and caudal to the oblique ridge the lateral wall is concave 

 and on the left side shows the impression of the arytenoid cartilage. This concavity is limited 

 in front by a ridge which broadens ventrad, there forming a broad elevation upon which termi- 

 nates the short arcus palatopharyngeus. Carte and MacAlister have noted the absence of the 

 uvula in B. rostrata ( = acuto-rostrata) , an observation confirmed by Turner, and also true of this 

 foetus. The former authors. describe a "peculiar, preepiglottic hoodlike fold" which they found 

 capable of being drawn over the epiglottis and inferred that it covered and protected the larynx 

 during deglution. Turner states explicitly that no such fold was present in his specimen, but 

 a comparison of the figures 1 leaves no room to doubt that both he and they had before them 

 the same structure, which Turner correctly designated velum. That he failed to recognize in 

 it the peculiar hood-like fold of Carte and MacAlister was in part due to their conjecture as to 

 its function, but especially to their location of the faucial orifice dorsal and not ventral to their 

 fold. In this, I believe, they were grossly mistaken, and that the probe in their illustrations does 

 not follow the faucial passage but is thrust through the velum itself. A consideration of the 

 position of the velum between the faucial canal and the pharynx reveals the possibility of such 

 an error, especially if they were dealing with material advanced in decomposition fourteen 

 days elapsed between the capture of the whale and the beginning of their dissection. 



As has been said, the faucial passage is not straight, but curves sharply ventrad in its caudal 



1 Carte and MacAlister, op. cit., pi. vi, figs. 5-9. 

 Turner, op. cil., pi. viii, fig. 31. 



