ZOOLOGY AND BOTANY, MICROSCOPYj ETC. 461 



not appear to bavo a special encysting envelojie, but tbo cellulose 

 reaction of tbe ordinary covering is very easy to detect. Tbe colora- 

 tion of tbe body is due to a closely jiacked unilamiuato layer of 

 cbromatojibores, wbicb are found in tbe periphery of tbe protoj^lasm ; 

 tbese bave a rod-like form, are arranged jjerpendicularly to tbe surface 

 of tbe body, and are set radially. Tbe stigma is a structure of some 

 size, and is always found in tbe longitudinal groove, wbicb is its 

 cbaracteristic position in tbe Cilioflagellata ; it occupies tbe wbole 

 breadtb of tbe groove, is concave at its anterior margin and convex 

 posteriorly, so tbat it is, on tbe wbole, like a borse-sboe in sbaj)e. An 

 irregular brownisb body of a fatty nature is not rarely seen in tbe 

 central protoplasm, and is especially large in tbe resting-stage. Tbe 

 relatively large spberical nucleus lies near tbe centre of tbe body, 

 and, during life, bas tbe appearance of a brigbt speck ; its structure 

 is finely plexiform, tbe nodal points being darker and somewbat 

 tbicker. A true contractile vacuole was not to be detected, but one 

 or more ordinary vacuoles were often seen on tbe ventral surface. 



Prof. E. Askenasy bas supplied an account of bis observations on 

 copulation and ecdysis. He states tbat be several times observed 

 copulating pairs of Glenodinium cindum ; tbougb not often found, be 

 bas sometimes, witb very ricb material, found one or two j^airs in 

 every drop examined ; tbey so attacb tbemselves to a point tbat tbe 

 binder pole of one is attached to tbe anterior of tbe other ; they 

 then move about together in the water, several times tbey separate and 

 again attach themselves, and the attachment becomes closer and 

 firmer ; the movement of a pair may last over an hour. This suddenly 

 ceases, but for a short time longer the long flagella may be seen 

 moving ; the zygote (if we may so call the product of coj)ulation) 

 remains quite still. The appearance of tbe zygote varies with 

 circumstances, but the form is always biscuit-like, and two eye-spots 

 and two nuclei are always to be seen ; at the point of junction there 

 is a distinct continuity of the protoplasm. In quiescent zygotes there 

 is a distinct doubly contoured membrane ; the further development 

 of the zygotes was not observed. As to tbe process of ecdysis, tbe 

 same observer notes tbat if swarming individuals be observed for an 

 hour or two, they will be seen after some time (at the most an hour 

 or two) to become quiescent and throw off their cilia; specimens 

 observed for several days were not seen to exhibit any further change ; 

 but at the end of a week several individuals were seen to bave cast 

 their cuticles, which w^ere found lying scattered about. One was 

 observed in the act ; there was a cleft at tbe side of the equatorial 

 groove ; when escaped it bad tbe appearance of a naked alga just 

 escaped from its mother-cell, and it may, therefore, be concluded that 

 at this time there is no firm membrane. Freshly escaped or tbin- 

 cuticled Glenodinia appear to copulate. 



After some observations on the marine species of Ceratium, Peri- 

 dinium, Gonyaulax, Dinophysis, and Prorocentrum, Prof. Biitschli passes 

 to tbe consideration of tbe genetic relations of the Cilioflagellata ; 

 he concludes tbat tbey are derived from the Flagellata, but he is not 

 certain whether there are differences sufficient to justify the establish- 



