INVERTEBRATA, CRYPTOGAMIA, MICROSCOPY, ETC. 91 



and will only add with him that further investigations in the domain 

 of embryology are necessary for the confirmation of his speculations. 



Dendroccela. Rhabdocosla. Nemertinea. 



Prostomese. Herostoniese. 



Monocelida. Mesostomese. Stenostomess. 



Convoluta. Dinophilus. 



Macrostomese. 



MicrostomesB. 

 Dicyemida and Gasterotricha. 



New Land Nemertine.* — Under the name of Geonemertes chali- 

 cophora Dr. Ludwig Graff describes a new form which he found in one 

 of the palm-houses at the Zoological Gardens at Frankfurt ; milk- 

 white in colour and from 10-12 mm. long, at the most, it resembles in 

 very many points G. palceensis.j There are in the skin some specially 

 remarkable deposits which take the place of the more common rod- 

 shaped bodies; these have the form of oval flattened bodies, which 

 are highly refractive and are principally made up of calcic carbonate. 

 Although dorso-ventral muscular fibres are present, they are arranged 

 somewhat irregularly and do not form distinct dissepiments as in the 

 marine Nemertinea (Hubrecht). 



As in Malacobdella and G. palceensis, and as in them only among 

 the Nemertinea, the oral orifice serves also as the orifice for the pro- 

 boscis. It is of interest to note that in this form as in most of the 

 Turbellaria the cells of the enteric epithelium are only distinct during 

 their resting (or hunger) stage, when they form more or less high 

 cylindrical cells, which are fringed on their enteric face by a layer of 

 hyaline protoplasm. When nutriment is introduced they elongate, 

 surround the food particles by amoeboid processes, and form a number 

 of vacuoles ; then they fuse comijletely with their neighbours, the 

 lumen of the tube disappears, and the whole cavity becomes tilled up 

 with a protoplasmic network, rich in vacuoles and containing the 

 food. This latter becomes dissolved and is diii'used, apparently 

 through tho basal end of the cells, into the perienteric fluid ; 

 at the termination of this process the enteric cells are seen to 

 have returned to tbcir original size. That the process of digestion 

 is really of this type in Geonemertes as in the allied forms, is rendered 

 certain by the evidence afforded by difierent sections through the 

 epithelium. The author notes the presence of three kinds of con- 

 nective tissue ; in tho cephalic region it is spongy, and made up 

 of highly refractive cells, between which there arc set delicate cells, 

 nucleated but witliout a membrane, together with muscular and con- 

 nective fibres ; more posteriorly and ventrally there is the second kind 



* 'Morpliol. Jahrlmc'li,' v. (lS7i>) p. 430. 

 t Seo this Journal, ii. (1879) j). 721. 



