1 82 Journal of Travel and Natural History 



Plantaginere, &c.). By this fact Sprengel considers the dicho- 

 gamia is proved. Following up Sprengel's ideas, Signor Delpino 

 carries them to their extreme limits. The following is pretty 

 much the course of his arguments : 



Generally speaking, the flower is an apparatus where all the 

 organs conspire to effect the impregnation, in other words, the 

 dichogamia ; and this is accomplished by means of two agents, 

 either wind or insects. In the flowers predestined to be fecun- 

 dated by the action of the wind, the anthers are, for the most part, 

 borne upon very long and exserted filaments, which gives better 

 purchase to the breeze, as we see in the Graminaceae and Planta- 

 gineae. The pollen is very fine and powdery ; often, as in the 

 Conifers, in extraordinary abundance to supply the great disper- 

 sion which takes place ; or as in the UrticaccK and allied families, 

 the anther, incurved at first by the elasticity of its filaments, starts up 

 like a spring, and scatters within a cloud of pollen. On the other 

 hand, in the flowers predestined to be fecundated by means of in- 

 sects, strange changes take place. The lively colours of the floral 

 envelope are, according to the thinkers who adopt this line of 

 argument, provided in order that the flowers may be discernible 

 at a distance by the insects. The profusion of pollen which is 

 generally met with in the plants, of which the impregnating agent 

 is the wind, is not present here. The pollen is oily and fatty that 

 it may the better adhere to the body of the insects. It may have 

 an effusion of odours and special smells to allure insects pre- 

 destined to act as scavengers. It may have a secretion of honey 

 to serv'^e as bait. There are most ingenious preparations to pre- 

 serve that precious liquor, as well from the injurious effects of the 

 atmosphere as from insects not predestined for the purpose, and 

 to direct the action of the same in such a way that they must 

 necessarily co-operate in the dichogamia. Under this hy]:)Othesis, 

 if in any flower we meet with brightly coloured parts and organs 

 secreting honey, we are, according to Signor Delpino, to rest per- 

 fectly assured that these two contingences exist there for no other 

 purpose but that of dichogamia. In especial, this is said of such 

 flowers as in their form seem to be or actually are what is called 

 anomalous, and which present spurs, fringes, horns, and appendages 

 of various kinds. Under Sprengel's theory, these anomalies are 

 nothing but more or less ingenious means for the advancement 

 of dichogamia. 



The result of a multiplicity of observations made by Signor 



