QUARTERLY CHRONICLE. 29 



development of the spermatozoa in certain insects and snails, 

 conclude the paper, which is illustrated by numerous figures. 



2. '^ On the Structure and Development of the Labyrinthulem,'''' 

 by Professor L. Cienkowski. 



In the last Chronicle a brief notice of this paper was 

 given, and the author's summary of his conclusions (vol. vii, 

 p. 277). 



The organisms in question Avere found in the harbour of 

 Odessa by Professor Cienkowski. His observations have led 

 him to recognise provisionally in them a new group, for 

 which he proposes the name of Labyrinthuleae. 



The members of this family are of microscopic dimensions. 

 They form thin, reticulate, colourless filaments, on which 

 fusiform bodies cumulate very slowly in variou.s directions. 

 The meshes of the net exhibit extreme differences in size and 

 shape. Another characteristic of these organisms consists in 

 the presence in various parts of imbedded globular or fusi- 

 form masses, from and into which the filaments appear to 

 arise and to be inserted. The reticular arrangement is often 

 wholly absent, when the filaments are disposed in an ar- 

 borescent manner. 



The network, as well as the arborescent ramifications, 

 spring from a central mass, which is sometimes as big as a 

 pin's head. And in these globular or irregularly formed 

 aggregations the Labyrinthuleae are met with on fragments of 

 wood encrusted with alga?, when they have been allowed to 

 remain in water for several days. 



The author has been able at present to make out only two 

 specifically distinct forms, in one of which the fusiform par- 

 ticles are of a yellow colour, and in the other colourless. 

 Including both in one genus, Labyrinthula, he names one 

 L. vitellina and the other L. macrocystis. 



In L. inteUina the central mass consists of an aggregation 

 of globules O'OlSmm. in diameter and having a very delicate 

 contour, and whose contents seem to derive their colour from 

 a reddish or bright yellow pigment. The entire mass is held 

 together by a delicate, finely -granular, cortical substance, 

 which often forms at the periphery a thin enveloping layer. 

 On the addition of alcohol this layer ajjpears in the form of 

 a delicate membrane at some distance from the shrunken 

 globules. The material of which it is composed is not 

 coloured either blue or brown by iodine. It is dissolved in 

 concentrated sulphuric acid, but the author has been unable 

 to perceive any proof of its containing cellulose. 



Besides the large central mass, there are observed in 

 various parts of the net smaller aggregations of globules, 



