OKNITHOEHYNCHUS PARADOXUS. 



819 



Fig. 412. 



the long series of living beings that have successively presented them- 

 selves to our notice must naturally expect that, between animals so 

 dissimilar in their economy as the Bird and the Mammal, intermediate 

 types of organization must occur, and that the transition from one to 

 the other is here, as elsewhere, gradually accomplished. 



(2419.) In this respect his expectations will be by no means disap- 

 pointed. The Ornithorhynchus paradoxus and the Echidna, animals 

 met with only in the continent of New Holland, are most obviously 

 connecting links between these two grand classes ; and, therefore, it is 

 with the history of these strange animals that we must commence our 

 examination of the Mammiferous generative system. 



(2420.) The Ornithorhynchus paradoxus 

 well deserves the specific epithet applied 

 to it by zoologists. It has, indeed, the 

 form of a quadruped, and its body is 

 covered with hair, and not with feathers ; 

 but its mouth is the beak of a duck ; and 

 upon its hind feet, which are broadly 

 webbed, the male carries a spur not unlike 

 that of a barn-door fowl. Having the 

 beak of a bird, how is the creature to 

 suck ? Nevertheless the females have 

 mammary glands well developed, but de- 

 stitute of prominent nipples ; so that the 

 mode in which the young animal obtains 

 the milk provided for it is even yet a 

 puzzling question. Does the Ornithorhyn- 

 chus lay eggs? or produce living young 

 ones ? This is a query that has not been 

 satisfactorily answered ; and its generative 

 apparatus is so nearly related to that of 

 an oviparous animal that even anatomy 

 throws but little light upon the subject. 



(2421.) Both in the male and female 

 there is, in fact, but one vent, that leads 

 to a cloacal chamber resembling that of a 

 bird; and the entire organization of the 

 sexual organs is rather that of an egg- 

 laying than of a viviparous creature, as 

 will be evident from the following details 

 respecting them. 



(2422.) The penis of the male Ornithorhynchus is perforated by a 

 ureiJiral canal, through which the semen passes, but not the urine; its 

 extremity, moreover, is terminated by two tubercles, giving it almost 

 a bifid appearance. This penis, when in a relaxed state, is lodged in a 



Male generative organs of 

 Ornithorhy nchus paradoxus. 



