184 Journal New York Entomological Society. [VoLxi. 



The Nervous System (Figs, i and 3) consists of si.x abdominal 

 ganglia, three thoracic, and the usual two head ganglia. 



The brain (Fig. 1) is not composed of distinct lobes as it isinAcri- 

 didse {Dissosleira). The procerebral, dentocerebral and tritocerebral 

 parts on each side form one continuous mass thick above {op. /. ) but 

 gradually tapering downward into the circumoesophageal commissure 

 {cos. c). The optic lobe regions {op. I.) are broadly united mesially 

 and from their outer upper aspects give off the optic nerves or optic 

 ganglia {op. gl.). Each of the latter is thickened basally, constricted 

 beyond the middle, and swollen terminally where it abuts against the 

 eye. The optic ganglia are much smaller than in the much larger- 

 eyed Acrididse. The ocellar nerves {oc.) are short and slender. 

 The antennal nerves {ant. n.) arise from the upper part of the dento- 

 cerebral regions. The labral nerve (/. //. ) and frontal commissure 

 (/. <r. ) have a common basal trunk on each side, but the labral nerve 

 soon separates, and goes downward to the labrum. From the frontal 

 ganglion (/. g.^ there goes ventrally upon the front of the oesophagus 

 a slender oesophageal nerve {iv. //.), and posteriorly upon the dorsal 

 surface of the crop a thicker stomatogastric nerve {sg. //.). The 

 oesophageal commissure {a;, c.) arises on each side just before the 

 bases of the circumoesophageal trunks {co;. c). 



The suboesophageal ganglion (Fig. 3) is of ordinary form and 

 gives off the mouth-part nerves as shown in the figure. 



The three thoracic ganglia are situated one in each segment. 



Of the six abdominal ganglia the first two are in the first and sec- 

 ond segments respectively, the third is in the fourth segment, the 

 fourth in the fifth, the fifth in the seventh, and the sixth in the eighth. 



The Circuhitory System (Figs. 9, 10 and 12) is rather easily studied 

 on account of the large size of the specimens. The heart consists of a 

 tube reaching from the posterior end of the abdomen forward into the 

 head. In each abdominal segment it presents a fusiform enlargement 

 or chamber (Fig. 12, ht. and <?<?.). 



The diaphragm extends throughout the entire length of the dorsal 

 part of the body, /. e., from the anterior edge of the prothorax to the 

 tip of the suranal plate (Fig. 12, dp.'). In the thorax it is a wide 

 sheet with slightly concave margins. It is widest in the prothorax, 

 tapering posteriorly in the meso- and metathorax. In the anterior 

 half of the abdomen it is a little wider than in the mesothorax, but 

 back of this it gradually tapers posteriorly, ending in a point beneath 

 the suranal plate. 



