THE PENCIL-TAIL. 



525 



line traversing the middle of the under surface, and that when the creature is walking, their 

 extremities do not project beyond the edges of the shelly covering. 



Like the armadillo-woodlouse, the Pill-millepede was formerly used in medicine, prob- 

 ably because it looks somewhat like a pill, and may be found among the old stock of drug- 

 gists' shops, mixed with the veritable armadillo. Both these beings feed on the same sub- 

 stances, namely, decaying animal and vegetable matter. It seems to be rather a gregarious 

 creature, as it is generally found in tolerable numbers in some favored locality. 



We now come to another genus, termed Polydesmus. This term is composed of two 

 Greek words, the former signifying "many," and the latter a "bundle," in allusion to the 

 numerous groups of limbs arranged along the body. In all these creatures the body is 

 covered with a hard skin, and the segments are flattened and lengthened at the sides. A 

 handsome species, called Polydesmus splendidus, is found in India, and mostly attains the 

 length of two inches. The color and general aspect of this species are rather striking. Inde- 

 pendently of the very deep depression of the segments, which has a very strange effect, the 

 color is bold and striking, being deep and very reddish-brown, diversified by an angular spot 

 of bright yellow placed in the hinder angles of each segment. The body is smooth and 

 slightly shining. When alarmed it is able to roll itself into a partial spiral, so as to present 

 merely the hard shelly armor to the foe, and to shield the limbs within the coil. 



To a new species belonging to this genus, I propose to give the specific name "granu- 

 latus," on account of the peculiar appearance of the body, which is thickly covered with very 

 minute raised tubercles of a white color, such tubercles being called granules in scientific 

 nomenclature. Perhaps I can give a better notion of the idea expressed by the word "granu- 

 lated," by mentioning that it could be rightly applied to such substances as shagreen. 



The general color of this species is rather dark drab, and it may be at once recognized by 

 the peculiar form of the segments, which are flattened and elongated even more than usual in 

 this genus, and are set at their extremities with three distinct teeth. The length of the speci- 

 men from which this description is taken is rather more than three inches. 



A species of this genus (Poly- 

 desmus complanatus), represented in 

 the accompanying illustration, is 

 found in Europe, and is not uncom- 

 mon in gardens. It is about three- 

 quarters of an inch in length, is very 

 nairow, and has thirty-one pairs of 

 feet. The genus is a very large one, 

 and contains a great number of exotic 

 species. The figure of the engrav- 

 ing is magnified. 



Before passing to the next large 

 family of myriapods, we may men- 

 tion the pretty little PENCIL-TAIL 



(Polyxenus lagurus\ a tiny creature which seldom attains a greater length than the twelfth of 

 an inch. It is found under the bark of trees, in clefts of walls, and in moss, and may be known 

 by the twelve pairs of feet, the bunches of little scales on the sides, and the white pencil at 

 the end of the tail. 



THE members of the curious family Julidse are very like those which have just been 

 described, but may be known from them by the fact that the edges of the segments are not 

 flattened and lengthened, but are continued in an unbroken circle. They feed mostly on 

 decaying vegetable matters, but have been seen to eat dead earth-worms and mollusks. 



They all exhale a peculiar and rather unpleasant odor, which is caused by a fluid secretion 

 in certain little sacs along the sides, two on each ring. The little apertures through which 

 this scented fluid exudes may be seen on examining the creatures closely, and by some of the 

 earlier writers they were mistaken, for spiracles, the sacs themselves being thought to be the 



POLYDESMUS. Potydestmu campkmatus. 



