1890.] 63 



shaped, acuminate at the apex, 8ubdeflexed, shorter than the elytra. Subgenital 

 lamina in $ bilobed. Length of the body, 28 — 35 mm. 



„ „ ovipoaitor, 27 — 30 mm. 



Its large size at once distinguishes this species from the other 

 British Locustidce, the only one approaching it is the rare D. verruci- 

 vorus, whose spotted elytra are at once noticeable. I have taken it or 

 know of its occurrence in many places along the south coast, from 

 Eamsgate to Land's End, and in the latter district saw it in large 

 numbers in September, 1889, and Mr. E. J. Pocock has given me spe- 

 cimens from Rhosili in Glamorganshire. Its stridulation is peculiarly 

 harsh and strident, making it easy to stalk it down, when its capture 

 may be best effected by seizing the hind-legs with the hand, care being 

 taken to secure them both, for if only one be held, the insect is sure 

 to break away, leaving its leg behind. Lo. viridissima occurs all over 

 Europe, and also in Northern Africa, Asia Minor, and in the Amur 

 district. 



vi.— THAMNOTRIZON, Fischer. 



Thamnotrizon, together with Platycleis and Decticus, belong to 

 the sub-family Decticidce, in which the prosternum is unarmed (in 

 British genera). The proximal joint of the posterior tarsi bears two 

 strong free processes (the " plautules "), which subserve the act of 

 springing. The anterior tibiae have on the upper-side three or four 

 spines ; and the posterior tibiae have two apical spines above and four 

 below (in British genera). 



In Thamnotrizon and Platycleis the anterior tibiae have three 

 spines above, while in Decticus there are four ; and Thamnotrizon 

 differs from Platycleis in having the elytra squamaeform. 



1. — Thamnoteizon cinereus, Linne. 

 Locusta cinerea, Linne, Syst. Nat., ed. xiii, p. 2071. 

 Thamnotrizon cinereus, Fischer, Orth. Eur., p. 205, tab. xiii, figs. 16, 



IGa-b, 17, 17* ; Brunuer, Prod, der Eur. Orth., p. 343. 

 Lo. aptera, Charpentier, Horfe Eut., p. 117. 

 Micropteryx aptera, Stephens, Mandib., vi, p. 12. 

 Acrida clypeata, Curt., Brit. Ent., ii, pi. 82. {Locusta), Pauzer, fase. 



33, pi. 4. 

 G-reyish-brown, with black markings. Head with the vertex broad, rounded, 

 separated from the frons by a transverse sulcus, where it has narrowed to less than 

 the breadth of the first joint of the antennae, ferruginous with faint fuscous 

 markings, and two dark fuscous spots between the antennae. Antennae not twice as 

 long as the body. Pi-onotum narrower anteriorly than posteriorly, with the posterior 

 margin truncate, in <? flat, in ? subconvex, with the remains of a median carina 

 indicated posteriorly ; side lobes roundly inserted, with a dark fuscous patch above, 

 sometimes only showing as a streak posteriorly, paler below, extreme margin paler 



