382 PHYSIOLOGY AND NATURAL HISTORY. 



them, and in this group still further anomalies are noticeable. While the greater 

 number of the florets are females, some of them are hermaphrodite, and others in 

 the same flower have a male and female floret, each with its distinct calyx within 

 the same glumes. The ovum is therefore, in this plant, exhibited in every form of 

 development, and its sex is so capriciously distributed as to favor the idea of some 

 phytologists that the sex is not determined at the origin of the ovu:«i, but by sub- 

 sequent casual circumstances. 



COI-EOrTERA. 



In the last number of the Proceedings of the Academy of Natural Sciences, of 

 Philadelphia. Dr. Leconte has added to his invaluable series of monographs of 

 North American Coleoptera one on the Pselaphidas. The paper contains an enu- 

 meration of the species and descriptions of those which are new. Of Dyschirius, 

 twenty-eight ; Acephorus, one ; Ardistomis, four ; Aspidoglossa, one ; Clivina, 

 twenty-seven ; Schizogenius, six. 



NKUROPTERA. 



Uhler has described seven new species of Libellula, inhabiting the United 

 States. 



MOLLUSCA. 



Lea describes a number of new species of Naiades, principally Uniones, from 

 Alabama, North Carolina, and other parts of the States. Under the rather curious 

 Leading of '■ Gnotic Species," he describes the following: 



Uhio Canadiensis. Testa lasvi, triangulari, subcompressa inoequilaterali, 

 postice obtuse angulata, valvulis subcrassis, antice crassioribus ; natibus subprc- 

 minentibus; epiderme lutea, postice radiata ; dentibus cardinalibus parvis, erectis 

 crenulatisque ; lateralibus longis, curvis lamellatisque ; margarita alba" et iridis- 

 eente. Hob. St. Lawrence River, near Montreal. 



THE CANADIAN HUMMING BIRD. 



During the present summer we were visited by Mr. John Gould, the distin- 

 guished Naturalist, whose chief object in his tour through Canada waa for the 

 purpose of studying the habits and manners of the species of Trochilus frequent- 

 ing this portion of the North American Continent. Shortly after his return to 

 England, at a meeting of the London Zoological Society, Mr. Gould detailed some 

 of the results of his observations. He arrived in Canada just before the period □ f 

 the migration of these beautiful little birds from Mexico to the north, and had 

 ample opportunities for observing them in a state of nature. Their actions he de- 

 scribed as very peculiar and quite different from those of all other birds; the 

 flight is performed by a motion of the wings so rapid as to be almost impercept- 

 ible; indeed, the muscular power of this little creature appeal's to be .very gi 

 in every respect [ependently of its rapid and sustained flight, it grasps 



small twigs, flowers, etc., upon which it alights with the utmost tenacity. It 

 pears to be most active in the morning and ev wing, and to j j -s fI > middle q 

 day in a state of sleepy torpor. Occasionally numbers that fifty 



or sixty may be seen in a single tree. When capfcw&v. ; uiy becomes 



tame that it will feed from the hand or mouth within half an hour. Mr. Gould 

 having been successful in keeping one alive in a gauze bag attached to his breast 

 button for three days, during which it readily fed from a small bottle filled with a 

 syrup of brown sugar and water, he determined to make an attempt to bring somt 



