THE CLASSIFICATION OF CUVIER. 



119 



(fig. 52, sg, g, og) united by nervous threads (c, ), and the intes- 

 tines are all included within one general uniform envelope." 



01' 



ac ao ny 



og n 



o g c 



m 



ma st 

 Fig. 52. 



The Articulata, which include the jointed animals, such 

 as insects, spiders, crabs, earth-worms, leeches, &c., he says, 



hd k glth b cr V i ov " have a nervous system, 



consisting of a double 

 cord (fig. 53, c, n) which 

 runs along the lower side 

 of the body, and is swollen 

 from space to space into 

 knots, or ganglions, (, g 1 , g 2 , g 3 , g 4 ). The envelope of the body 



Fig. 52. Helix albolabris. Diagramic representation of the common Snail. 

 2 diam. ac, ac 1 , the abdominal cavity ; sh, the shell ; t, the larger pair of feelers, 

 with an eye (e) at the tip of each; ft, the smaller pair of feelers; m, mouth; st, 

 stomach ; in, intestine ; ml, posterior opening of in ; sg, the superior ganglion 

 of the head ; g, the inferior, or sub-oesophageal ganglion ; c, the nervous collar ; n, 

 ng, the foot nerves ; og, the oesophageal, or gullet nerves ; h, the auricle, and h 1 

 the ventricle of the heart ; ao, the aorta, or main artery ; pv, vein from the lung, 

 or pulmonic vein ; ov, the ovary, or egg-bearing organ ; ov 1 , the oviduct, or 

 emptying conduit of ov ; o, exterior aperture of ov 1 ; r, the fertilizing gland, or 

 male element of the reproductive organs ; ma, the matrix. Original. 



Fig. 53. Sphinx Liguslri. Lin. The Privet Hawk-Moth. Natural size. A 

 longitudinal, sectional view, an, antennae, or feelers ; M, the head, or first joint 

 of the body; th, the thorax, consisting of the 2d, 3d, and 4th rings; b to 6 1 , the 

 eight rings of the abdomen ; /, the base of the legs ; p, the tubular proboscis : </', 

 the gullet; st, stomach ; cr, crop; f, intestine; a, posterior end of i; h, h 1 , Ifl, 







\ % *- < 



