ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 79 



while alongside of them in the same colony individuals are found 

 which are wholly green. Then, again, how are the so-called red and 

 dark-coloured Stentors to be disposed of, both of which have been 

 detected in the United States ? For these, indeed, it may be claimed 

 that degenerating chlorophyll would be capable of producing the red 

 colour of the first, and that feeding on very dark coloured algee might 

 develope the latter. In spite of all this, however, there remains a 

 residuum of facts which cannot be disposed of on any theory of sym- 

 biosis or parasitism, and this is especially the case with those forms 

 which, as in Stentor, show three distinct types of coloration, viz. the 

 diffuse bottle-green, that caused by coloured green granules, and the 

 colourless ; all of these differences at the same time being indicative, 

 together with other features, of very distinct species. 



As to the aggregation and development of Bacteria about living 

 Infusorians, this the author noticed in a colourless marine species, 

 Zoothamnium alternar,s, and the same fact has been observed by Stein. 

 Both Stein and behave noticed bacilli mostly in this relation^ to other 

 living colourless Infusorians, but in the case of dead and colourless 

 Infusorians the remains of the animals are usually attacked at one side 

 and gradually invaded by bacilli and micrococci, and altogether 

 independently of any peculiarly local oxygen-yielding source in the 

 vicinity. 



"If there exist green Vorticellce which have the green colouring 

 matter arranged diffusely in the ectoplasm in one species, and in 

 another confined to distinct granules as observed in the species 

 described, it is fair to presume that, as in the cases of the three species 

 of Stentor, we also have here to do with two very distinct species of 

 bell-animalcules. It is also fair to assume that if the different 

 species present their colouring matters in diverse conditions and modes 

 of arrangement such matters may have correspondingly different 

 functions, and that it does not necessarily follow that the green gra- 

 nules even are a sure indication of the presence of true chlorophyll, 

 though it may simulate that of the plant in its r'^lation to the stratum 

 of plasma covering the cell-wall. Why not suj)pose that some of 

 these colouring matters of Infusorians have a function similar to 

 haemoglobin ? It would, however, be much easier to suppose that the 

 quasi-chlorophyll grains of V. cldorostigma were truly of the nature of 

 chlorophyll than to assume as much regarding the diffuse green colour 

 as observed in the ectoplasm of a supposed variety or closely affiliated 

 species of V. campanula, as has been done by Engelmann." 



New Ciliated Infusorian.* — L. F. Henneguy describes, under 

 the name of Ascohius lentus, a new genus of infusorians which lives 

 fixed at the base of a chitinous sheath ; the animal has the form of a 

 Bursaria, belongs to the group of the Heterotricha, and in its mode of 

 life resembles Freia, from which, however, it differs owing to the 

 absence of membranous lobes to the lateral parts of the peristome. 

 The specific name refers to the remarkably slow movement of its 

 cilia. It is of fresh-water habitat ; and the author found it in the 

 Jardin des Plantes at Montpellier. 



* Arch. Zool. Exper. et Gen., ii. (1884) pj). 412-5 (1 pi. not published yet). 



