OETHOPTERA. 559 



Acryclii are always laid in rudely regular clusters, in the 

 ground." (Seudder.) 



The nervous system closely resembles that of the Neurop- 

 tera ; it is in all three stages composed of three thoracic, and 

 six or seven abdominal ganglia, extending the whole length of 

 the body, and united by double commissures. The splanchnic 

 system, or analogue of the great sympathetic nerve in verte- 

 brates, is highly developed in the Acrid ii and in Gryllotalpa, 

 having in front two pairs of ganglia, and posteriorly one or 

 two, while in the Bl attar ice and Pliasmida the single 

 nerve is most developed. 



Organs of hearing are stated by Siebold to occur in the 

 Acridity consisting of two fossjB or conchs, surrounded by a 

 projecting horny ring, and at the base of which is stretched 

 a membrane resembling a tympanum. On the internal surface 

 of this membrane are two horny processes, to which is attached 

 an extremely delicate vesicle filled with a transparent fluid, 

 and representing a membranous lab3'rinth. This vesicle is in 

 connection with an auditory nerve, which arises from the third 

 thoracic ganglion, forms a ganglion upon the tympanum, and 

 terminates in the immediate neighborliood of tlie labyrinth l)y 

 a collection of cuneiform, staff-like bodies, with very finely 

 pointed extremities (primitive nerve-fil)res?), which are sur- 

 rounded by loosely aggregated, ganglionic globules. The 

 Locustarim and Gryllidm have a similar organ, situated 

 in the fore legs directly below the coxo-femoral articulation. 

 M. Ilensen confirms the accuracy of this description in 

 the " Zeitschrift fiir Wissenschaftliche Zoologie," vol. xvi, 

 1867. 



Tiie highly developed alimentary canal has the crop (pro- 

 ventricuUis) separated by a deep constriction from the oesoph- 

 agus, and the gizzard is provided internally with from six to 

 eight rows of horny denticulated plates situated on ridges, 

 with numerous smaller teeth betAveen, so that the whole num 

 ber of teeth amount to 270. The stomach is of even width, 

 not usually making more than one-half of a turn, or one turn ; 

 its cardiac extremity is provided Avith from two to eight coeca. 

 The salivary glands are highl}' developed, "consisting of two, 

 four, or six botryoidal masses, situated in the thorax, and hav- 



