262 OBSERVATIONS ON THE NATURAL FAMILY 



with those, and which I considered secondary in this order, 

 though they occupy the place of the primary vessels in other 

 families : and it is this inverted disposition, indicated in the 

 greater part of the class by the primary being the only 

 vessels existing, which I have considered as of material 

 importance in determining the limits of Compositae, though 

 by no means as affording an essential practical character for 

 the whole class. 



In the passage quoted from M. Cassini (the only one I 

 can find relative to the subject in the memoir in which it 

 occurs), the existence of five nerves or vessels in the tube 

 of the corolla, alternating w T ith its latinise, is stated, but 

 their division and disposition in the laciniae are not 

 noticed ; it is at the same time to be inferred from the 

 terms of the passage, that no other vessels exist in the tube 

 of the corolla : and it is equally evident that, so far from 

 announcing this disposition of vessels as a discovery, or 

 peculiar to the order, the author rather considers it either 

 as a fact already known, or as the usual structure. That 

 M .. Cassini was not then aware of the importance of the fact 

 which he had imperfectly stated, appears likewise from his 

 having, many months after his memoir was read, and at a 

 time when he says he had finished his analysis of the 

 corolla, proposed a name for the class, taken from a sup- 

 posed peculiarity in the structure of the filament, a name 

 which he is now inclined to abandon for one derived from 

 the disposition of vessels in the corolla. 



so] Since my attention has been again turned to the sub- 

 ject, I have endeavoured to collect all that has been observed 

 on the nerves or vessels of the corolla of Compositae, a 

 brief account of which may be not altogether without 

 interest. 



The earliest notice I have been able to find is contained 

 in a passage (in page 170) of Grew's Anatomy of Plants, 

 where, in speaking of syngenesious flosculi, he says, " they 

 are frequently ridged, or as it were hem'd like the edge of 

 a band." And his figure of a magnified floret of the 

 common Marigold, in tab. 61, gives a tolerable idea of the 

 marginal vessels of its lacunae. Grew however takes no 



