200 Description of the Plates. > 



possessed by the males^ and the median emarg-ination of 

 the supra-anal dorsal plate with which the cerci articulate. 

 These cerci appear to represent the processes which the last 

 seg-ment of the post-abdomen so frequently gives oflp in 

 certain lower Crustacea, as e. g. Apus, Cyclops, Lynceus, 

 Caligus; and, like the line of fission between the second 

 pair of maxillae and the three basal joints supporting the 

 antennary flagellum, to be structures by possessing which 

 the Orthoptera resemble the Crustacea, see p. iii, sujjra j 

 and Eathke, Morphologic, p. 115. 



d. Nerve ganglion developed upon the nervus recurrens, and 



seen to give off a nerve on either side, which passes back- 

 wards upon the crop and has itself fusiform dilatations of 

 a ganglionic character developed upon it. From the tri- 

 angular ganglion, d, a nerve has been figured and described 

 as passing off" to the salivary glands. 



e. Common duct communicating with the two lobes of the 



dendritic saHvary gland. The ducts of the two salivary 

 glands fuse mesially with each other, in the angle formed 

 by the convergence of the ducts of the two salivary bladders 

 or reservoirs; and the common duct thus formed by the 

 ducts from the two glands, fuses subsequently with the 

 common duct from the two reservoirs, so that the two 

 compound ducts find an outlet into the mouth by means 

 of a short common canal. The figure does not accurately 

 reproduce this arrangement, which cannot be demonstrated 

 to the unassisted eye. All the four ducts and the compound 

 ducts have their internal chitinized coat spirally thickened 

 so as to resemble tracheae. 



f. Salivary bladder. 



g. Gizzard communicating inferiorly with the chylific stomach, i, 



through the intermediation of a short segment of small 

 calibre. 



h. Whorl of eight coeca, analogous probably to a liver, arranged 

 round the commencement of the chylific stomach, and re- 

 sembling the simple hepatic coeca of Hedriophthalmatous 

 Crustacea, 



i. Chylific stomach, smooth externally as is the upper half of 

 the homologous segment in the Gryllotalpa, and limited 



