858 



THE YOUNG NATURALIST. 



probably resembles the last. 



Pood Plants.— It is said to feed on Dog 

 violet. Sweet violet, and Wild heartsease 

 (Viola canina, oderata, and tricolor). 



Times of Appearance.— Similar to the 

 last species. The imago appears in July ; 

 the egg is laid in July or August ; the young 

 larva hybernates, to re-appear in spring, 

 when it feeds up. The pupa has been found 

 in June. 



Habitat.— A rarer species than either 

 Paphia or Aglaia. It is taken in open places 

 in woods, and also on hill sides near them, 

 and it is also recorded as oecuring on moors 

 and commons. It is more of a Southern 

 species than either of the above, though it 

 occurs in some localities in the more northern 

 counties of England, and has been taken in 

 Scotland. Several localities in Ireland are 

 given where it has been taken. It occurs all 

 over Europe, except in the Polar regions, and 

 also in Asia, where that continent borders on 

 Europe, but it does not seem to penetrate 

 far into the interior. 



Variation.— The species varies both by 

 the enlargement and coalescing of the black 

 spots, and by a change in hue of the ground 

 color. A very beautiful specimen is in Mr. 

 Gregson's collection, in which the greater 

 portion of both wings is black. Mr. Stevens 

 has one with the spots as usual, but the 

 ground color is a very pale drab. Others 

 occur in which it is a rich mahogany brown, 

 while various intermediate varieties are 

 found. Several varieties of the underside 

 have been named. Clebdoxa, Ochs., has the 

 usual silvery spots of the underside, pale 

 yellow, or very slightly silvered. This form 

 has sometime; occurred in Eigland, but is 

 commoner in Greece and Sicily. Chloi'odipfe, 

 M.S., is greener on the- underside than the 

 normal form. It occurs in S t din and Anda- 

 lusia, and has more silvery central spots. 

 Cieotlippc, Stand., another Spanish variety, 

 resembles the last, except in the want of the 

 silvery spots. 



Parasites.— None known to us. 



EXPLANATION OF PLATE 8. 



1 Succinea Putris. 



2 Helix Nemoralis. 



3 Do. (with animal.) 



4 Bulimus Acutus. 



j 5 Planorbis Corneus. 



6 Physa Fontinalis (enlarged.) 



7 Physa Hypnorum. 



8 Lymnaea Limosa. 



9 Ancylus Fluviatilis. 



10 Bythinia Tentaculata. 



11 Valvata Piscinalis. 



12 Neritina Fluviatilis. 

 I 13 Anodonta Cygnea. 



: 14 Cyclas Cornea, exterior and interior. 



j ___ 



CONCHOLOGY. 



j LAND AND FRESHWATER SHELLS. 

 By FI. T. Robsom, Stockton-on-Tees. 

 (Continued from page 31 i.J 

 Genus, Physa. 

 The shells of this genus are oval, light, and 

 transparent, with the whorls reversed, the 

 animals have a pair of long slender tentacles, 

 at the inner base of which the eyes are placed. 

 There are two species, Fontinalus and Hypno- 

 rum. 



Fontinalis. — This is an oval shell about 

 j a third of an inch long, with reversed whorls, 

 j long and transparent, pale horny, the spire is 

 raised but small, the aperture large ; the 

 j portion of the animal seen through the shell 

 j is prettily marked with light spots, the ten- 

 I tacles are thread-like, widened out at the 

 base ; the most marked characteristic is 

 however in the mantle, which, when the 

 animal is fully emerged, is turned back over 

 the outside of the shell, both at the front and 

 back, each lobe being divided into several 

 finger-like appendages laying close to the 

 shell. This is a lively little mollusc and will 

 readily display its curious mantle if 

 placed in a basin of water. It may be found 

 in all parts of the country, in ponds, streams, 

 canals, &c. 



