186 Linnean Society. [Feb. 6, 



to be the same with Ech. pulchellus, Risso, and a variety Ech. deco- 

 ratus, Agass. It is also Ech. miliaris of Grube, but very distinct 

 from the true Ech. miliaris. 



Gen. CiDARis, Lam. 

 Species of Cidaris Hystrix, Lam., were frequently met with, but 

 perfect specimens are not so common. They are occasionally, how- 

 ever, found in considerable numbers and appeared to be gregarious, 

 between thirty and forty living examples having been taken in a 

 single dredge in seventy fathoms water off Cape Krio in Asia Minor, 

 the site of the ancient city of Cnidos. The author gives a particular 

 account of the differences between this species and Cid. papillaris of 

 the British and Norwegian seas, and observes that it possesses the 

 power of climbing up branching bodies by means of its spines alone. 

 He thinks it possible that the perforated tubercles of this genus may 

 have reference to this habit, the additional ligament giving additional 

 firmness to the long spine. 



February 6. 



R. Brown, Esq., V.P., in the Chair. 



Read " Descriptions of the Nests of two Hymenopterous Insects 

 inhabiting Brazil, and of the species by which they were constructed." 

 By John Curtis, Esq., F.L.S. 



The materials for this paper were obtained by Mr. Curtis from a 

 collection in the possession of Lord Goderich, to whom it was pre- 

 sented by the Right Hon. Henry Ellis, on his return from his late 

 special mission to Brazil. 



The first insect described belongs to the family of Tenthredinidce 

 and to the genus Hylotoma of Klug. But this extensive grouj), as Mr. 

 Curtis has already remarked, affording sufficient grounds for further 

 generic subdivision, he has distinguished the present species by the 

 following name and characters : — 



DiELocERus, Curt. 

 AntenncE articulo S^io in mare furcato, piloso ; in foemina simplici. 

 Tibice ante apicem espinosse. Clypeus profunde emarginatus. Labrum 

 orbiculare: mandihulcE graciles, acuts, altera denticulo intevno mi- 



