770 SUMMARY OF CCJRRENT RESEARCHES RELATING TO 



the species requires further investigation. A rather full account is 

 given of the incompletely known Dendroijlirya radiata, first described by 

 iStrethill Wright. Gromia gracilis is a new species with an oviform or 

 spherical, colourless test ; the protoplasm is colourless, and the pseudo- 

 podial stalk has no roots. There aie a number of vacuoles, one con- 

 tractile vesicle, and one nucleus. Keproduction is effected by transverse 

 and probably also by longitudinal division. Trichosphroeiiim sieholdi is 

 described at some length, and a special group is made f jr it, which is 

 called Trichosa, and thus defined : — -Pseudopodia lobate ; test flexible, 

 with pore-canals, but no large orifice and bilaminate; the outer layer 

 consists of special organic rodlets, the inner of a chitinous membrane. 

 The group tjccupies a low position among the Testacea, and appears to 

 form a connecting link between the Perforata and the Amceb^a. A 

 description is given of Biomyxa vagans, but it remains to be shown 

 whether it is an adult Ehizopod, or a developmental stage in the life 

 of a Protist. A new species of Arnoeha — A. prehensilis — is shortly 

 described. 



Nuelearia delicatula.* — M. A. Astari finds that, in its vegetative 

 phase, Nudearia delicatula is spherical, pyriform, oviform, and elongated, 

 but it is often irregular in form, and may be lobed. The protoplasm is 

 generally lich in vacuoles, and contains several nuclei. Needle-shaped, 

 simple, rarely branched, pseudopodia are given off from the body, which 

 is otten surrounded by a mucous investment, the surface of which is 

 covered with granules. 



The ground-mass of tbe body is formed by a homogeneous and 

 hyaline substance, the hyaloplasm ; in this, small granules are imbedded, 

 which too^ether make up the granular plasma ; this latter is distributed 

 regularly through the body * as it generally reaches the periphery there 

 is no division of the body into an outer and an inner layer. The number 

 of food- vacuoles varies from four or five t J so many that they give a 

 frothy appearance to the body, and they vary also considerably in size. 

 The author has failed to find contractile vacuoles. 



Specimens may be quite colourless, or bright red, yellowish or 

 brownish ; and the coloration of the body is dependent on the food. 

 The gelatinous investment is coloured reddish by Hanstein's anilin- 

 violet, and can, as a rule, be seen only in free-living individuds; 

 Nuclearise which are put into the moist chamber lose their investment, 

 and become nake.l. 



The process of ingestion of food is very interesting ; when a short 

 filament of Oscillaria is seized, the organism ordinarily draws the alga 

 as a wh(de into the interior of its body ; to effect this it approaches the 

 al»a and touches it with its pseudopodia, and then gradually flows round 

 it • if the al«ar tilament is too long, the Nudearia either seizes part of it, 

 when the rest remains outside its body or breaks off, or it takes it in a 

 different way. It places itself at the end of the filament, and the 

 granular protoplasm begins to be depressed ; after a short time the cell- 

 membrane disappears at the point of junction, as though it had been 

 destroyed; the granular structures of the cell-contents alter their 

 position, and pass into the interior of the body of the Nudearia. Later 

 on, the same fate happens to the second cell, then to the third, and so on. 

 In another case the author observed that a Nudearia had attached itself 



* Zool. Anzeig., xii. (lSi^9) pp. 408-16. 



