382 Mr. H. J. Carter on the " Tuhulations Sahleuses " 



to arrange themselves in so limited a space : it can be clearly 

 seen that the wings have thrown themselves into a multiplicity 

 of closely packed transverse folds, representing increments of 

 growth in length, and that these, again, have disposed them- 

 selves, in groups, in wavy (longitudinal) folds representing 

 growth in breadth ; so that the wings, plaited and folded up in 

 this complex manner, present a superficial resemblance to the 

 surface of a much-convoluted brain or to a portion of a trans- 

 verse section of a Labyrinthodont tooth. 



This mode of development of the wings obtains in all Ortho- 

 pterous insects, upon larvae of which these observations are 

 mainly based — at least in some Neuroptera {Termes), and 

 probably universally in the groups which Westwood, years 

 ago, collectively termed the Homomorphic Insecta. 



XXXVII. — Note on the " Tuhulations Sahleuses " of the Etage 

 Bruxellien in the Environs of Brussels. By H. J. Carter, 

 F.R.S. &c. 



[Plate XVIII.] 



In the ' Annales de la Socl^t^ Malacologique de Belgique,' 

 t. ix. pi. iii. 1874, M. A. Rutot published an excellent paper 

 on the '' Gr^s Fistuleux et Tuhulations Sahleuses de I'dtage 

 Bruxellien " in the environs of Brussels, chiefly dwelling 

 on the fossil sponge-spicules found about them ; and thus 

 attention has been directed to these interesting objects, which 

 otherwise might have remained in abeyance for an inde- 

 finite period. 



Knowing the interest which I have taken in the Spongida 

 both recent and fossil, my kind friend M. Ernest Vanden 

 Broeck, of Brussels, obtained from M. Rutot a copy of his 

 paper, and, together with some of tlie sand containing the 

 sponge-spicules, forwarded the same to me in April 1876, 

 following it (as I had expressed an opinion somewhat different 

 from the conclusions to which M. Rutot had arrived) by a 

 box containing several specimens of the " tuhulations sa- 

 hleuses " themselves, for my examination. 



These specimens, which were preceded by a letter and 

 sketches from M. Vanden Broeck explanatory of the contents 

 of the box &c., reached me in August 1876 ; and having had 

 many engagements to fulfil since them, my examination of 

 them has necessarily been postponed to the present time (Feb. 

 1877). 



There are eighteen specimens of the " tuhulations," with 



