792 AHACKNIDES— SCORPION. 



on different animals. In general, they are carnivorous, and suck the blood 

 of their prey or animals. A small number only feed on vegetable matters. 

 Many have mandibles which exercise the office of a sucker ; and others have 

 an isolated sucker, often, however, joined with mandibles and palpi. The 

 terrestrial species are in general solitary animals, and of a forbidding aspect, 

 and many of them shun the light, and live in concealment. Several of these 

 are poisonous, and their bite dangerous. Lamarck divides the class of Arch- 

 nides into three orders, viz : First, Those destitute of antennae, furnished 

 with branchial sacs for respiration, and with six to eight eyes. Second, 

 Those destitute of antennae, with branched trachea for respiration, and with 

 two or four smooth eyes. Third, Those with antennae and gangliated tra- 

 chia for respiration ; while Lalreille arranges the class into tAvo orders, ac- 

 cording to the characters of their branchial apparatus. 



Order I. Pulmonari^, — With pulmonary sacs for respiration; a heart 

 and distinct vessels. 



Order II. Tkacheari>e. — Respiring by tracheae, and the organs of cir- 

 culation indistinct. 



THE SCORPION. 1 



There are four principal parts distinguishable in this animal; the head, 

 the breast, the belly, and the tail. The scorpion's head seems, as it were, 

 joined to the breast; in the middle of which are seen two eyes ; and a little 

 more forward, two eyes more, placed in the fore part of the head ; these 

 eyes are so small, that they are scarcely perceivable; and it is probable the 

 animal has but little occasion for seeing. The mouth is furnished with two 

 jaws ; the undermost is divided into two, and the parts notched into each 



• The genus Scorpio has two large palpi in the form of arms, the last joint thickest, 

 and in the form of forceps : mandibles short, narrow, and didactyle ; jaws short, rounded ; 

 eyes six or eight ; body oblong, divided into many segments, with a long, knotty, tail ter- 

 minated in an arched sting ; two pectinated and moveable plates under the belly at the 

 base of the abdomen ; lour spiracles on each side ; eight feet. 



