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lude of men/' These extremes are most readily recognized ; and so 

 are some among the more striking of the intermediate grades of being: 

 some of their relationships and affinities are likewise patent to our 

 finite understanding ; and something of the plan upon which they are 

 arranged has been discovered : but beyond the development of a com- 

 paratively small number of facts, more or less isolated, we cannot at 

 present boast of having advanced very far in our researches. 



One thing, however, is certain, that these gradations of being by no 

 means proceed in linear series. "The chain of being" is a most 

 unapt expression as applied to the works of Nature. Nor is the simi- 

 litude of the territories on a map a much more appropriate one ; since 

 the affinities do no not lie on a plane, but are most intricately inter- 

 woven in all directions. 



A brief mention of a few of what have not unaptly been considered 

 the osculant or connecting forms we have referred to may not be out 

 of place. One of these is the little barren strawberry, as it has been 

 called — one of the earliest heralds of spring. This is a strawberry in 

 everything but its fruit, and was formerly included in the genus Fra- 

 garia, under the name of F. sterilis. The receptacle, however, does 

 not become succulent, as in a true Fragaria, but remains dry, with the 

 uncombined carpels reposing upon its surface. This plant has in 

 consequence been removed from the genus Fragaria ; and after having 

 been considered a Comarum by some authors, rests for the present 

 under the appellation of Potentilla Fragariastrum. 



Drupaceous plants among the Rosales, are essentially distinguished 

 from the Pomaceae by their solitary carpels, and the presence of hy- 

 drocyanic acid in their tissues ; but some Pruni have a tendency to 

 produce several carpels, and the formation of hydrocyanic acid in 

 Cotoneaster microphylla, and some other Pomaceae, demonstrate the 

 affinity of that order with the Drupaceae. 



Then, again, the common garden bean and a peach-tree are very 

 unlike in appearance, and they belong to two apparently distinct so- 

 called natural orders. Nevertheless, Detarium, a fabaceous plant, 

 produces a legume so very like the drupe of the Drupaceae, that were 

 it not for the different position of the odd sepal in the calyx with 

 respect to the axis, the two could scarcely be distinguished. And the 

 close affinity between the Fabaceae and the Drupaceae is still further 

 indicated by the abnormal structure of the fruit in Prunus spinosa and 

 P. Padus, met with in Scotland by Mr. W. Thomson, as recorded in 

 the Proceedings of the Botanical Society of Edinburgh (Phytol. iv. 

 278). 



