220 



Ontario side of the Ottawa, thougli I liave sometimes found dead 

 shells. The nearest station to Ottawa where I have met with it is in 

 Hull, on the northeily slopes of the hill beyond the Aylmer road toll- 

 gate. A visit to this locality is usually rewaided with two or three 

 niatuie living examples. Young shells are not nearly so rare. I took 

 eleven in the afternoon of the 26th of April, 1884. They were from 13 

 to 16 mm. in diameter. Previously I used to leave immature shells of 

 thi.s, as of other species, where I found them, but having learned that 

 helices were easily reared, determined to try the experiment with these 

 young J/, saij'd. I [)laced them with mature shells of the same and 

 other s]iecies in a glass-covered box, half filled with rich loose mould, 

 moss and withered leaves well moistened ; and kept them plentifully 

 supplied with food in the form of lettuce, cabbage and flour paste, all of 

 which they appeared to relish exceedingly. They grew rapidly, and by 

 the 1st of July had begun to form a thick peristome. The tooth on the 

 basal margin did not appear for some time. Still later the tooth on 

 the parietal wall was formed, a thin transparent film at first, increasing 

 in thickness and diminishing in length and breath as layer after lajer 

 was day by day deposited by the little artificer with as much precision 

 as if the highest intelligence directed its operations. By Se|)teniber 1st, 

 the shells v/ere all fully formed, but quite thin. The additioji matle in 

 caj)tivity is lighter in color than the portion for:ned previously. It 

 consists in no case of moi*e than a whorl, but as this is the last anil 

 largest it increases the diameter of the shell more than a third and 

 brings it to from 1 9 to 21-3 mm. 



Whether from eggs deposited by these or the older specim»^ns I 

 cannot tell, but early in August I first noticed in the box a number of 

 young shells a little more than two millimetres in diameter. They 

 appeared to groAv but slowly, yet by NovemV^er had increased fully a 

 whorl. On the Idth of that month, while collecting in the Laurentides, 

 I found hibernating a dozen or more immature M. sayii precisely like 

 those I had taken near the city the previous April. The lines of 

 accretion formed immediately before hibernation were of a reddish colour. 

 Between this dark band and apex, another band less prominent is distin- 

 guisiiable at the point reached in one season ly the shells I had reared 

 from the egs. From these facts I infer that M. sayii attains maturity in 



