STRUCTURE.] OVULE. 391 



13. Of the Ovule. 



The Ovule (Plate V. fig. 16. to 26.) is a small, semipellucid, 

 pulpy body, borne by the placenta, and gradually changing 

 into a seed. Its internal structure is difficult to determine, 

 both in consequence of its minuteness, and of the extreme 

 delicacy of its parts, which are easily torn and crushed by 

 the dissecting knife. It is doubtless owing to this circum- 

 stance chiefly, that the anatomy of the ovule was almost 

 unknown to botanists of the last century, and that it has 

 only begun to be understood within ten or twelve years, 

 during which it has received ample illustration from several 

 skilful observers. Brown, indeed, claims to have pointed out 

 its real nature so long ago as 1814 ; but the brief and incom- 

 plete terms then used by that gentleman, in the midst of a 

 long description of a single species, in the Appendix to 

 Captain Flinders' s Voyage, unaccompanied as they were by 

 any explanatory remarks, prove indeed that he knew some- 

 thing of the matter, but by no means entitle him to the 

 credit of having, at that time, made the world acquainted 

 with it. The late Mr. Thomas Smith seems to deserve the 

 honour of having first made any general remarks upon the 

 subject : of what extent they exactly were is not known, as 

 his discoveries, in 1818, were communicated, as it would seem, 

 in conversation only ; but it is to be collected from Brown's 

 statement that they were of a highly important nature. At 

 a later period the structure of the ovule received much atten- 

 tion from Brown, in England ; Turpin and Adolphe Bron- 

 gniart, in France; and Treviranus, in Germany; by all of 

 whom the subject was greatly illustrated. It was, however, 

 to Mirbel, who, by collecting the discoveries of others, 

 examining their accuracy, and combining them with nume- 

 rous observations of his own, first produced a full account of 

 the gradual development and the different modifications of 

 the ovule that we were indebted for by far the best early 

 description of this important organ. His two papers were 

 read before the Academy of Sciences at Paris, in 1828 and 

 1829, and still deserve to be consulted notwithstanding some 



