Mr. Walker on the British Chalcidites. 177 



M. Ehrenberg* considers the separation and isolation of 

 the stomachic vesicles as surprising only to those who have 

 not observed earth worms cut into pieces. These pieces, he 

 observes, let them be ever so minute, contract at each extre- 

 mity in such a manner that but very little of the contained 

 juices escape, and a similar effect is produced by the contrac- 

 tion of the isolated stomachs of the Infusoria. One fact un- 

 doubtedly is more forcible than all arguments ; and I only re- 

 gret that that of a vesicle containing fragments of Oscillatoria 

 has not presented itself several times to the observer ; for with 

 respect to the alleged stomachs without contained aliments, 

 even when they appear slightly coloured, the false comparison 

 with the pieces of earth worms will not suffice to prove to me 

 that the globules are not part of the gelatinous substance of 

 the Infusoria, sincje I have frequently seen these globules co- 

 loured, either from their having a tinge of their own, or that 

 this effect was the result of an optical illusion or of a phaeno- 

 menon of accidental colours. 



XXI. — Descriptions of British Chalcidites. By Francis Walker, 



F.L.S. 



[Continued from vol. ii. p. 355.] 



Sp. 45. Cirrospilus Murcia, Mas. Cyaneus, abdomen cupreum, antennas 

 nigro-picece, femora nigra, tibice j)ice&, tarsi fusci, prolibies fulva', ales 

 sublimpidce. 



Obscure cyaneus : oculi et ocelli rufi : antennas nigro-picese ; articuli l us 

 et 2 US nigro-cyanei, hie apice piceus ; abdomen cupreum : pedes fusci ; coxae 

 nigra?; femora nigra; tibiae piceae ; genua fulva ; propedum femora apice 

 fulva : alae sublimpidae ; squamulae piceae; nervipallide fusci. (Corp. long, 

 lin. f ; alar. lin. 1.) 



Found near London. 



Mas. Corpus sublineare, nitens, scitissime squameum, parce hirtum : caput 

 transversum, breve, convexum, juxta tboraci latum ; vertex sat latus; frons 

 abrupte declivis: oculi mediocres : antennae filiformes corporis longitudine, 

 pilis longis vestitae ; articulus l us gracilis, sublinearis; 2 US longicyathiformis ; 

 3 US brevis ; 4 US , 5 US et 6 US longi, lineares ; clava longifusifonnis, acuminata, 

 articulo 6° duplo longior : thorax ovatus, convexus : prothorax brevissimus, 

 supra vix conspicuus : mesothoracis scutum latitudine longius ; parapsidum 

 suturae remotse, bene determinate ; scutellum breviconicum : metathorax 

 transversus, mediocris : petiolus brevissimus : abdomen sublineare, planum, 

 * Die Infusionsthierchen, 1838, p. 361. 



Ann. Nat. Hist. Vol. 3. No. 16. May\§2>9. o 



