1901.] LARYNX or CEETAIK WHALES. 289 



is, of course, formed by the tip of the epiglottis, also thick and 

 rounded. 



This aperture is, then, perfectly well defined; it measures 

 two inches by one inch, but it is rather wider at the ventral than at 

 the dorsal (arytenoid) end. As seen from the side, this tube is 

 somewhat peniform, the free end terminating in the thick lips 

 just referred to, the arytenoids projecting beyond the epiglottis. 



I have seen no trace or indication of a sublaryngeal pouch in 

 Cogia, such as has been described by Murie (1871) for Eisso's 

 Grampus, by Watson and Young (1879) for Beluc;a, and by Sir 

 "Wm. Turner (1886) for Mesoijlodon. 



Murie writes (p. 127), near the base of the epiglottis there is 

 " a median orifice leading into a moderate-sized pouch, which fills 

 in great part the angle of junction between the enlarged epiglottis 

 and the thyroid cartilage ; " and Turner says (p. 165) that between 

 the forks of the bifurcated epiglottis and the upper border of the 

 thyroid cartilage there is a shallow mesial pouch, lined by mucous 

 membrane, which freely communicates with the interior of the 

 larynx. 



With these statements before me I looked carefully for this 

 pouch in Cogia, but it is absent. There is no space or " angle " 

 between the epiglottis and the thyroid such as Murie describes, 

 and there seems to be actually " no room " for any such pouch. 

 At any rate, there is none, nor is there any glandular tissue to 

 represent it, which Murie describes and figures (p. 128) in relation 

 to the pouch. 



In Cogia the lining membrane both of the arytenoids and of the 

 epiglottis is smooth ; the median ridge on the latter forms a slight 

 depression on each side (which is precisely what occurs, too, in 

 Balcenoptera), and in the lower half of these lateral grooves the 

 mucous membrane is pitted ; these small pits and depressions are, 

 however, present only on the sides, not in the middle line as 

 Murie describes for Eisso's Grampus. Nor does he mention any 

 pouch in Gl. melas (1867), nor do I find one in ZipJiins (see 

 below). 



The Cartilages. 



The tracheal rings are here complete, and the upper ones 

 present certain irregularities that will be better understood by 

 reference to the figures than by a description. 



About one inch below the larynx the trachea gives off on the 

 right side a bronchus — the third bronchus — as in most other 

 Odontocetes. 



The cartilages, as will be seen by a glance at the figures, differ 

 very considerably in form and proportions from the corresponding 

 parts in the Rorqual. 



The thyroid cartilage (PI. XXV. fig. 4, T.) is represented by tiuo 

 separate pieces, a right and a left, which meet ventrally. These 

 two halves may be termed for convenience the thyroid plates or 

 alse. Each thyroid plate presents a " body " and coruu, and forms 



