292 DR. J. MUEIE ON THE OEGANIZATION OP THE CAAING WHALE. 



as they are, they yet retam a iihysiological importance of no mean value. In them can 

 rest no power of expression whatsoever ; withal, what a development of parts which in 

 higher mammalia are devoted mainly to such a faculty ! It would seem as if there were 

 no end to utilitarian purposes. The same tool which in the Cetacean is perforce 

 adjunct to the respiratory act, is transformed in the Euminantia to a grasper of herbage, 

 in the Suidae to a digging-instrument, in the Elephantidse to a tactile flexible limb, and 

 so on. 



Again, in the flsh-like form of body of Whales, there rules similarity of spinal 

 tendiao-muscular distribution. It is easy to trace the homologues of the great lateral 

 piscine muscles and even their segments (myocommas). For whether studied in the 

 longitudinal direction, or in cross section, there can be recognized counterparts of fibre, 

 tendon, and flesh as found in the predacious Shark and others of the finny tribe. 



There is one piece of organic mechanism in which, so far as Globiceps is concerned, 

 I do not quite follow the descriptive evidence of previous anatomists. I allude to the 

 motions of the larynx. As I find it in this form, it is difiicult to conceive how it is 

 thrust upwards and downwards, and fii-mly constricted at every expiration and inspira- 

 tion. The chief directions it seems capable of moving in are fore-and-aft, with a 

 limited power of elevation and moderate dilatation and approximation of the aryteno- 

 epiglottic funnel. It appears to me that the upper portion of the funnel at all times 

 rests in the posterior nares, upright, and with an obliquity corresponding to the direc- 

 tion of the inferior nasal channel. This leaves one of the pharyngeal passages wider 

 than the other, along which the greatest bulk of the food must pass. It is during 

 deglutition, not respiration, that the strongest action of a grasping and elevating nature 

 takes place, in this presenting a certain agreement with the second phase of the act in 

 ourselves. At such times perfect closure of the funnel by compression of the circular 

 fibres of the superior constrictor, and elevation through contraction of the longitudinal 

 ones, blockades the postnares and sends the food on to the oesophageal sphincters in the 

 rear. When expiration and inspiration are about to take place, it is quite obvious that 

 were the naso-laryngeal sphincter forcibly to grasp the aryteno-epiglottic tube, and 

 powerfully drag it upwards, as some assert is the case, the consequence would be 

 closure of the breathing-tube itself. I conceive that in the performance of respiration 

 there is a firm but moderate contraction of the naso-pharyngeal parts, sufficient only to 

 steady the aryteno-epiglottic funnel, and prevent passage of air into the gullet. At the 

 same time those laryngeal muscles which act as dilators open the cartilaginous tube, 

 and give free vent to the outgoing and incoming air. Meanwhile also the muscular and 

 resilient cartilaginous parts at the spii-acular orifice play in active unison. 



The function of the retia mirabUia, with which Whales above all other vertebrata are 

 copiously furnished, is still a matter of conjecture. Such men as Hunter, Cuvier, and 

 Breschet have looked upon them in the light of reservoirs, to store up an excess of 

 arterial blood, needful during the animal's long submersion — a kind of supplementary 



