254 Miscellaneous. 



after all, as originally supposed by Ehreuberg. Their gradual 

 diminution in size towards the posterior pole, where they are nearly 

 atrophied, would seem to indicate that they were in some way 

 related to the power of the organism to move in a definite direction, 

 the cells of the anterior end being provided with the best developed 

 visual, sensory apparatus, or whatever it may be. If it should prove 

 possible to show that these "■ eye-spots " are reall}' sensory organs 

 in Volvox, as all the facts which have been here noted would seem 

 to indicate, it vpould be one of the few instances known of a plant 

 possessed of visual or sensory organs of any kind, unless we except 

 some such plants as the Venus' fly-trap. 



The speaker stated that he had been unable to find any notice of 

 any of the features of Volvox which are here described ; all of the 

 figures to which he had had access in standard works were entirely 

 erroneous from their authors having completely overlooked these 

 very salient and important features of this remarkable plant. This 

 should therefore be regarded as his apology for bringing a very 

 common organism to the notice of the Academ}- and to the renewed 

 attention of the microscopists who take pleasure in studying it. It 

 is to be hoped that some one who is skilled in such vrork will be 

 induced to take up the study of Volvox anew and publish a well- 

 executed drawing of a colony in which the facts here recorded are 

 adequately represented. This is all the more desirable in that, if 

 Volvox is really a plant, its psychological history should be as much 

 a matter of interest as its singular beauty and its intricate methods 

 of reproduction seem to have been. — Proc. Acad. Nat. Sci. Fhilad. 

 May 21, 1889, p. 138. 



On a Gall produced in Typhlocyba rosae, Linn., hy a Hymenopterous 

 Larva. Ey M. A. Giard. 



During last October the trunks of the horse-chestnuta in the 

 Luxembourg Garden were covered with thousands of dead specimens 

 of Typldocyha ros(T, with the wings half open, and slightly attached 

 to the bark, as if thej' had been killed by an Entomophthorean. 

 The under surface of the leaves also bore a great number of dead 

 specimens of this insect. By microscopic examination 1 could not 

 detect any trace of Cryptogams. However, as R. Thaxter has 

 lately noted the facility with which Typhlocyba rosce and mali when 

 infested by Entomoplithora splice rospenna, Fres., completely discharge 

 their spores, I thought I must have come upon the scene too late, 

 and left a more complete observation to the summer of the present 

 year *. I must confess that my curiosity was much excited by the 



* Typhlocyba rosce lives usually upon roses, apple-trees, and other 

 Rosaceous plants, and often causes great mischief in gardens. I do not 

 think that it has ever been indicated upon the horse-chestnut. In spite 

 of a careful examination I iiave been unable to find characters clearly 

 separating the variety (esculi from the type. M. Lethierry, whose know- 

 ledge of the Hemiptera is so great, ascribes the few differences observed 

 to the action of the parasites upon the Typhlocyba. However, the Typhlo- 

 cybce which have become adapted to the horse-chestnut seem to neglect 

 the roses planted in the vicinity. 



