376 Bone's Memoires Geologiqucs et Paleontologiques. 



monograph is mainly on the systematic relations of these 

 creatures, but the flesh-and-blood naturalists are not wholly 

 forgotten, as incidental notices of habits and manners are 

 mingled with the systematic remarks. 



So minute are the objects described, that Cyclas rivicola, 

 the largest of the three species of Cyclas, is only lOj lines 

 long, 8^ lines high, and 6i lines thick; and, in the genus 

 Pisidium, four of the species do not exceed 2 lines in length, 

 1^ in height, and 1^ in thickness. These facts are noticed 

 for the sake of quoting the following remark : — " The dis- 

 covery of Pisidium pulchellum, and some other minute spe- 

 cies, which, though of frequent occurrence, remained for a 

 long time unnoticed by conchologists, may be attributed to 

 the use of a peculiar net, invented by Professor Henslow, 

 about the year 1815. This instrument, being constructed of 

 the finest wire gauze, enables the collector to strain the water 

 more thoroughly than by any other method previously at- 

 tempted, and thereby to separate the very smallest shells 

 from the mud in which they are immersed." It is hoped 

 Professor Henslow will early oblige the readers of this 

 Magazine with a drawing and description of so useful an 

 invention. 



Scmerhy, J"., jun.: The Mushroom and Champignon illustrated, 

 compared with and distinguished from the Poisonous 

 Fungi that resemble them. Small 4to, 6 pages of letter- 

 press, and 5 plates of coloured figures. London, Sowerby, 

 1832. 



Concise, clear, useful, and cheap ; but only four species are 

 contradistinguished: — Agkricns campestris, the true edible 

 mushroom, from A, Georgii, St. George's mushroom, or 

 white caps ; and A. pratensis, the true champignon, from A. 

 virosus, the poisonous agaric, which considerably resembles 

 it. A. Gear (rii is stated to be called " St. George's mush- 

 room, because it is said 'to grow up about St. George's 

 day,' and that it is by no means so wholesome as the true 

 mushroom, because of its dry and tough texture ; but it is 

 not poisonous, as it has sometimes been thought to be." 

 ^garicus virosus and its varieties, one of which, being found 

 covered with a sort of gluten in wet weather, is sometimes 

 called A. glutinosus, are all deemed fatally poisonous. 



Boue, A., Foreign Secretary of the Geological Society of 

 France : Memoires Geologiques et Paleontologiques. 

 Treuttel and WUrtz. 



Of this work, it appears, one volume, consisting of 369 



