34 



Crouhtrg at Natural 



abundant. It measures from two and a half 

 to three inches in the expanse of the fore 

 wings, which are of a rich brown colour, 

 with numerous irregular spots and streaks 

 of cream white ; the hind wings bright red, 

 with blue-black spots ; the thorax brown, 

 with a red neck-band, and the abdomen red, 

 with blue-black bars. The insects belonging 

 to this genus are observed to vary consider- 



ably in their markings, and the present spe- 

 cies is no exception to the general rule ; 

 some having the brown and blue-black por- 

 tions more or less obliterated, whilst in 

 others they are sometimes almost entirely 

 predominant. The Caterpillar is dark brown, 

 and very hairy, the hairs on the back dusky, 

 and those on the neck and sides reddish, the 

 head black : its food is nettles, chiukweed, 

 lettuce, strawberries, &c. When full fed it 

 spins itself a web, wherein, at the latter end 

 of April, it changes to the Chrysalis state ; 

 and the Moth appears about the end of June 

 or beginning of July. 



ARCTIC FOX. ( Viilpcs lagopus.') A small 

 species of Fox, inhabiting the high northern 

 latitudes, and justly celebrated for the 

 beauty and fineness of its fur. [See Fox.] 



ARCTIID^. A family of Lepidopterous 

 insects, belonging to the general section 

 HETEROCERA, comprising those species 

 which have the wings deflexed in repose, 

 the posterior pair not extending beyond the 

 costa of the anterior. The antennas of the 

 males are strongly serrated ; the spiral tongue 

 is either very small, or obsolete ; and the 

 labial palpi are generally short and obtuse 

 at the tip. The caterpillars vary much : in 

 some species they are thickly hairy ; some 

 are furnished with long fasciles of hairs ; 

 and some are naked, but variously tubercled. 



They feed upon the external parts of plants, 

 and enclose themselves in cocoons when 

 about to undergo their transformations. The 

 types of the family are distinguished by their 

 larvae being very thickly clothed with long 

 hairs, whence they have obtained the name 

 of "woolly bears." Such are especially the | 

 larvae of the various species of Tiger Moths, i 

 and others nearly allied to them, which are I 

 well known, and considered as being amongst 

 the most beautiful of all the species of Moths ; 

 their fore wings are ornamented with white, i 

 brown, or black, and the hind wings red, j 

 with black or blue markings. Some of these 1 

 caterpillars are extremely destructive, par- I 

 ticularly to fruit trees and hedges. Great j 

 alarm has been created at times when they j 

 were particularly abundant ; and, indeed, 

 their polyphagous habits on such occasions 

 may justly be dreaded. The larva of some 

 species are furnished, in addition to the long 

 slender hairs all over the body, with several 

 short, thick, truncated tufts of hair on the 

 back as well as at the sides ; the majority of 

 these produce species not materially differing 

 in the sexes ; but some, forming the genus 

 Oryyia, have females with the smallest ru- 

 diments of wings, and large swollen abdo- 

 mens, and which are exceedingly sluggish 

 in their habits, whilst the males are con- j 

 stantly on the wing, flitting about in the ! 

 hottest weather of autumn. The family like- ! 

 wise comprises several other genera differing 

 widely in the appearance of the sexes, or ano- 

 malous as respects their transformations. 



ARCTOCEPHALUS TJRSENUS. The i 



Ursal ; a species of Seal, from the north ot ! 

 the Pacific Ocean. It is eight feet long, has \ 

 no mane, and varies in colour from brown to 

 wliitish. [See SEAL.] 



ARCTOMYS. [See MARMOT.] 



ARCUATA. A section of the genus Can- 

 cer, of which the true Crabs are the type. 

 [See CRAB.] 



ARDEA. The Heron [which see]. 



ARDEID^E. A very extensive family of 

 birds, formed for wading, and generally 

 seeking their food on the margins of rivers 

 and lakes, and in marshes, where they obtain 

 fish, reptiles, and even small mammalia. 

 They are characterized by having very long 

 legs, with a strong, straight, pointed, and 

 compressed bill ; in most species finely 

 toothed ; the upper mandible usually notched 

 towards the tip ; a furrow passing from the 

 nostrils, which are linear, to the apex. 

 They in general build and breed in societies, 

 but always wander alone in search of food, 

 and after the breeding season lead a solitary 

 existence. They have ample wings, and 

 many of them are adorned with elegant 

 plumes and crests. [See HERON, STOKK, &c.] 



ARENICOLA. A genus of Dvrsibran- 

 chiata, or Cuvier's second order of the class 

 ANNELIDA. The gills are of an arborescent 

 form, on the rings of the middle part of the 

 body. The best known species (Arenicola 

 marina) is common on our coasts, where the 

 fishermen, who dig for it as bait, know it by 

 the name of the Lob- worm. It is almost a foot 



