naturalists’ calendar. 
237 
above, and whitish underneath, and about an inch in diameter. In stagnant 
ponds, and low marshy ground the Limneus palustris, (7) is often numerous, the 
shell is about three quarters of an inch long, of a brown horn colour, rather 
opaque, it may be found feeding on the plants growing in those situations be¬ 
twixt five and six o’clock in the morning during this month, often in company 
with the Segmentina nitida (8) from which it may be distinguished by its size, 
this last being scarcely £ of an inch in diameter, highly polished and smooth, of 
a chesnut or reddish brown colour, fiattish or semi-transparent. 
Insects.— All the carniverous water-beetles (Natural Order, Dytiscites, inclu¬ 
ding the well known genera, Dytiscus, Colymbetes, Acilius, Hydroporus) in 
swimming, move both hind legs simultaneously, striking out with great vigour in 
the same way as a frog; whereas the herbivorous water-beetles (Hydrophilites; 
genera Hydrous, Hydrophylus, Helephorus, &c.) in swimming, move their hind 
legs alternately, thus making weaker strokes, and progressing in the water much 
slower. The Dytiscites also porrect their antennae in swimming, and conceal 
their palpi; the Hydrophilites, on the contrary, porrect their palpi, and conceal 
their antennae. Ent. Mag. 
29 
Dragon Flies and numerous other insects, make their appearance this 
month, as the Cow-lady, (Coccinella) Flesh fly, (Musca vomitoria) Four Spotted 
Dragon Fly, (Libellula qnadrimaculata,) The Great Dragon Fly, (/Eshna gran- 
dis, Fig. 29,) and many species of Butterflies and Moths. 
