26 EXPLANATION OF ANATOMICAL PLATES. 



Fig. 20. Claws of Asihts : o, central filaments ; ts, membranous expansion of tlie terminal joint, ad- 

 vanced beneath the claw s. 

 Pigs. 25, 26 : showing the upper and uuder side of the domestic cricket (Acheta arachnoidea). 

 Pig. 27. Maxillary palpi [be) of the cricket; b, galea. 



1 i 28. Lower lip of the crieket ; a, mentum; d, labium; f, additional articulations, divided into 

 two, three, or more lobes ; cc, apparently 3-jointed palpi, yet the basal joint enveloped or 

 laled in the lip. 



Fig. 20. Mandible< of the grasshopper (Aayditnn) : b, molar plate. 



Fig. 80. Man lilies of the cricket- 

 81, 32. Forms of antennae. 



Fig. D:!. Serrated antenna?. 



Fig. 34. Lamellifonn antenna?. 



Fig. 35. Pectinated antennae.; bipeetinatcd, if it produces two long teeth, instead of one ; and flabcl- 

 late, when the branches are very long, and flattened like the rays of a fan. 



Fig. 41. Setaceous antenna; : filiform, when the antenna; arc of unequal thickness ; moniliform, as in 

 fig. 4 2 ; ensiform, when tapering, and angnlatedat the sides ; subulate, when short, and 

 .pointed at the tip ; fusiform, when narrowed at the two extremities and thickened in the 

 centre, as in fig. 43 ; olavate, v. hen they gradually thicken at the top, as in 37 and 35; 

 geniculate, when bent as in 39 ale ; capitate, when terminated in a knob or head, as- 3G , 

 plumose, when the lateral filaments go off from a shaft, like those of a feather ; nodose, 

 when the joints are thickened in various parts like knobs ; vertieillate, when whorls of hairs 

 are placed at equal distances upon the joints ; fasciculate, when the hairs are gathered in 

 bundles upon each joint ; seopifcrous, when a single bundle is placed upon one joint ; 

 palmate, when the antenna; are short, broad, and divided by deep divisions ; auriculate, 

 when one of the basal joints is dilated into a shield or ear partially covering the rest ; 

 fissile, when they are terminated by a cleft knob ; ramose, when several of the joints throw- 

 out branches ; furcate, when there are two branches like a fork ; aristate, when the antennae 

 are terminated by a fine bristle, as in the order Musca ; dentate, when the joints are armed 

 with short spines ; cylindrical, when they arc of equal diameter throughout ; prismatic, 

 when they resemble a prism, or are formed of three sides. 



II. PARTS OF THE DIGESTIVE APPARATUS.— PLATE B. 



Fiss. 2, 3. a shows the esophagus, beginning in fig. 3 just behind the head, and terminating in an en- 

 largement which is the crop ; or, if the crop is absent, it terminates in the gizzard d. The 

 esophagus is a simple tube, except in the lepidoptera. 



Pig. 4 c represents the position and relation of what has been denominated a sucking stomach. The 

 gizzard is shown in position, fig. 2 c. The true stomach, or, as called by some entomologists, 

 the chylific ventricle, is seen in figs. 2 & 3 d : in this organ the food becomes semifluid or 

 pulpy, and remains until chylification takes place. The intestine begins as represented in 

 fig. 3, where the lateral tubes are inserted : it preserves a course more or less contorted, as 

 n at f ; and in some instances it is enlarged or inflated, as at g. The '.'tecum is seen 

 at g fig. 2. 



