I08 NATURE STUDV. 



matter, when every maturing capsule sheds seeds innum- 

 erable? Some of them, at any rate enough to ensure the 

 perpetuation of the species, will be sure to find favorable 

 conditions and so fulfil their ofhce. 



It may be of interest to note the places in the families of 

 flowering plants occupied by the aristocratic family of or- 

 chids and the useful family presently to be considered. 



The five largest families and the approximate number of 

 species they contain are as follows : 



Compositse, thistle familj^, 10,000 to 12,000 species. 

 Leguminosse, bean family, 6500 species. 

 Rubiaceae, madder family, 5500 species. 

 Orchidaces, orchid family, 5000 species. 

 Gramine£e, grass family, 3500 species. 



In the matter of distribution over the globe the five fam- 

 ilies differ greatly. The thistle, bean and grass families are 

 of very wide and general distribution ; the orchid family is 

 most abundant in tropical, though fairly well represent- 

 ed in temperate regions; the madder family is almost entirely 

 tropical, being very poorly represented in temperate zones. 

 The only genera of this family with which we are familiar 

 in New Hampshire are Houstonia, including the well- 

 known "bluets," Cephalanthus, the button bush, Mitch- 

 ella, the partridge berry, and Galium, including bed- 

 straw, cleavers, goose-grass and wild liquorice. 



From the standpoint of usefulness, which, of course, 

 means usefulness to man, the differences are fully as great 

 as in distribution. Leaving out the madder family, which 

 is of little consequence in this part of the world, we have 

 remaining four great families, two of which are useful, two 

 useless, or nearly so. The orchid family has a certain es- 

 thetic value, derived from the beauty of some of its flowers; 

 it may also be called useful in so far as it incites wealthy 

 and otherwise indolent Englishmen to discover new species 

 and so add to the general stock of knowledge. The this- 



