164 FOURTH REPORT — 1834. 



The Munotremata, which are involved in quite as much 

 obscurity as the Marsujiialia, have been for some time, but 

 particularly within the last two years, a subject of great contro- 

 versy amongst the first naturalists. Although belonging more 

 to the department of anatomy, it will be necessary to say some- 

 thing of this discussion, from its great importance to the science 

 we are considering. The controversy has chiefly turned upon 

 the existence or not of true mammary glands in these animals, 

 and their consequent claims to be admitted among the Mam- 

 malia. 



Lamarck was the first to maintain, in 1809*, arguing from the 

 supposed absence of these glands, and the consequent probability 

 that the Monotremata\ were oviparous, that thej* ought to form 

 a separate class. This opinion was subsequently adopted by 

 Geoffroy in the Bulletin de la Soc. Phil. 1822 J ; and also by 

 Van der Hoeven in a memoir on the Ornithot'Uynchns, pub- 

 lished in 1823 in the Nov. Act. 8)C. Nat. Cur.'^. In 1824, 

 Meckel announced, in Froriep's Notizen, that he had dis- 

 covered these glands, and in 1826 he published his Anatomy 

 of the OrnithorhynchusW, in which their nature and situation 

 were more fully illustrated. In the course of the same year (1826) 

 Geoffi-oy endeavoured to show^, that the supposed mammary 

 glands seen by Meckel were not truly lactiferous, but analogous 

 to certain glands which he had observed in the genus Sore.v**. 

 In 1827tt Meckel replied to Geoffroy, adducing further argu- 

 ments in support of his former opinion. The same year Geoff- 

 roy published a memoir on the structure of the genital and 

 urinary organs in the OrnithorhynchHs\1^, from an examination 

 of which he was still led to infer that it was certainly oviparous. 

 This belief was soon after much strengthened by the receipt of 

 information from Dr. Grant of the supposed discovery of the 

 eggs of the Ornithorhynchns^^, which circumstance gave rise to 



* Phil. Zool, torn. i. pp. 145 and 342. 



t The name of Monotrejnala dates from 1803, when Geoffroy, who first ap- 

 plied it in consideration of the peculiar structure of the genital organs, made 

 simply a new order of these animals. See Bull, de la Soc. Phil., tom. iii. p. 225. 



I p. 95. § tom. xi. part ii. p. 351. 



II Ornithorhynchi Paradoxi Descriptio Anatomica. fol. Lipsiae, 1826. 

 ^ yinn. des Set. Nat., tom. ix. p. 457. 



** These latter glands form the subject of a memoir published by Geoffroy, 

 in 1815, in the first volume of the Memoires du Museicm ; to which I refer the 

 reader. 



tt Archiv.fur AnaL, band x. p. 23. XX Mem. du Mus., tom. xv. p. 1. 



§§ See an account of the discoverj', accompanied by a description of these 

 eggs, in the Edinb. New Phil. Journ. for Jan. 1830, p. 149. 



