THt: CAlTADIAN ENTOMOLOGIST. Ill 



BOOK NOTICES. 



The Inter-relation of Insects and Flowers. — During the last 

 eight years there have appeared from the pen of Mr. Charles Robertson, 

 of Carlinville, 111., several most interesting articles on the inter-relation of 

 insects and flowers. The titles are as follows : — 



Botanical Gazette. 



1886. Notes on the pollination of Asclepias. 



1887. Insect relations of certain Asclepiads. 



1887. Fertihzation of Calopogon parviflorus. 



1888. Effect of the wind on bees and flowers. 



1888. Zygomorphy and its causes : I — III. 

 1889-93. Flowers and insects : I — XL 



Trans. Am. Ent. Soc. 



1889. Synopsis of North American species of Oxybelus, 

 1891-93. Descriptions of new species of North American Bees. 



Trans. St. Lotiis Acad, of Science. 



1 89 1, 1892. Flowers and uisects : Asclepiadaceae to Scrofulariace^. — 

 Umbelliferae. — Labiatse. 



Mr. Robertson began in 1886 to study the visits of insects to flowers, 

 and by his persevering observations he has succeeded in collecting an 

 enormous number of facts which he has published mostly in the Botani- 

 cal Gazette, and in the Transactions of the St. Louis Academy of Science. 

 He has studied the subject especially from a botanical point of view, and 

 has given particular attention to the attractions offered to insects by the 

 flowers of different species of plants, to the peculiarities of arrangement 

 of their different parts, to their coloration, and to the modifications which 

 many flowers seem to have undergone from their being constantly fre- 

 quented by certain species of insects. Such studies have nevertheless an 

 immediate bearing on entomology, as they give us at the same time an 

 insight into the purposes of insects in visiting flowers, into their habits of 

 feeding and collecting either nectar or pollen, or both at once, and into 

 the intelligence they display in order to attain their end The close 

 attention thus necessarily given to insects lias had besides the natural re- 

 sult of causing Mr. Robertson to discover that many of those insects 

 which he was observing in his locality, Carlinville, 111., had not even been 

 described. Therefore, he found it " necessary at first to pay particular 



