2 ON THE STRUCTURE AND GROWTH OF SEEDS. 



eyes are the principal judf>;es, and a long habit of viewing 

 tliininutive objects will detect truth, sooner than much 

 knowledge. As I have before written ou this subject, it will 

 not be wholly in my power to avoid repetitions; but they 

 shall be as few as possible. 

 Cause of the It appears to me, that the manner in which seeds are ge- 

 nMst;;kesof nerally taken for dissection is the cause of most of the mis- 

 takes disseminated. Most physiologists begin by dissecting 

 full grown seeds; and, Ibllowing their first impressions, ap- 

 plying the names, and appropriating the descriptions, to 

 such parts of the seeds (in that state of growth) as appears 

 Young seeds 4 best to suit them. But as there is not in nature any thing 

 essentklly. *^ niore different, than a very young seed, and an old one ; it 

 is ten to one that the names are misapplied, as the vessels 

 of most consequence in the earliest stages are wholly lost in 

 an old seed, while another set of vessels usurp [almost) their 

 places: by which means the nourishing vessels, at the ter- 

 mination of their cari^'er, are often mistaken for the impreg- 

 nating duct; while the vessel of life (before it reaches the 

 Numerous in- heart) is taken for the radicle. So easily are these mistakes 



stances of mis- ^^ ^^ traced in most works of this kind, that T could eive 

 takes fiom tins . J' 



source might innumerable examples to prove my assertion, were, it not 

 be atlduccd. better to show the origin of the mistake, and endeavour to 

 rectify it; proving plainly, that to begin by dissecting full 

 grown seeds is truly commencing at the wrong end. 

 The send To gain a perfect knowledge of the seed, it is necessary 



shouMbeexa- ^^ detect its first appearance in the seed vessel; in this si- 



mined in itb . J, , • i • , , 



earliest stage, tuation become perfectly acquamted with the names and 



and pirsued ^g^g ^f ^,.^^,^ part; and thence trace them upwards in their 



through Its ' . ^ 



whole pro- dally improvement, till, removed from the seed, they are 



grass. fixed in the earth. To distinguish the vessels designed for 



the seed only from those intended to complete \\\e fruity is 

 cf the first consequence: for, as the seed is the principal 

 object of Nature's care, it is the first perfected in its vessels; 

 but, after they are all ready for the completion of the em- 

 bryo, it takes a long time to prepare the young plant for its 

 first appearance ; and this time is employed by Nature in 

 the completion of the fruit. This has, in most instances, 

 two or three different vessels, not in any manner useful to 

 the seed, found at this time invigorating the fruit; and as 



these 



