4 THE AMERICAN BOTANIST. 



compass-plants or rosin-weeds {Silphiuin) belong, and it is 

 made noticeable by the fact that as the seeds ripen, the re- 

 mains of the disk florets fall away leaving the broad black 

 fruits radiating from the disk like some new and strange com- 

 posite flower. The most interesting feature of these strange 

 objects, however, is to be noticed shortly after the seeds have 

 matured. By this time the thick and fleshy involucral scales 

 have dropped, the bark of the peduncle has loosened and the 

 outer part of its central cylinder has separated into its compon- 

 ent bundles each of which now turns outward bearing a fruit 

 at its apex. Although the composite nature of the flower- 

 cluster is perfectly familiar to botanists, it is seldom that 

 nature so clearly indicates it. In the case of the compass- 

 plants the likeness to the closely related Umbelliferae is particu- 

 larly striking. 



SELECTING A MICROSCOPE. 



BY A. E. WARREN. 



TO the amateur naturalist blessed with a purse of average 

 length the acquirement of a compound microscope is 

 a subject fraught with many scare crow dollar-marks. Tend- 

 ing against the popularity of the instrument to an even greater 

 degree is the belief that its actual use bristles, cactus-like, with 

 technical difficulties. There is just enough truth in each of 

 these notions to keep this noble instrument out of the hands of 

 the great majority of home scientists who work con amore and 

 have only a limited supply of money to spend on hobby-rid- 

 ing. That neither idea is wholly true the writer affirms on the 

 strength of intermittent personal experience extending over a 

 score of years coupled with more than the average number of 

 financial vicissitudes. 



The manufacturers and dealers are to some extent to 

 blame for misconceptions in regard to the necessary outlay. 

 WMiile an immense amount of reading matter purporting to 



