194 Misce Uaneo us . 



Endamoeba blattce. 



Erne Art Proteus, Seibold, Beitr. z. Naturges. d. wirb. Thiere, 1839, 



fide Stein. 

 Ambbenform, Stein, Organismus d. Infusionsthiere, 1867, ii. p. 345. 

 Amceba Blattce, Biitschli, Zeitsch. f. wiss. Zoologie, 1878, xxx. p. 273, 



Taf. xv. fig. 26. 



Initial form globular, passing into spheroidal, oval, or variously 

 lobate forms, mostly clavate, and moving with the broader" pole in 

 advance. Protoplasm finely granular, and when in motion more 

 or less distinctly striate. Nucleus spherical, granular, with a large 

 nucleolus. Distinct food particles commonly few or none. Size 

 of globular forms 0*054: millim. to 0*075 in diameter ; elongated 

 forms 0-075 by 0"06 to 0*15 by 0*09 millim. Parasitic in the 

 large intestine of Blatta orientalis. 



The Endamoeba blattce affords a good example of a primitive 

 active nucleated organic corpuscle, or a so-called organic cell with- 

 out a cell-wall. In the encysted condition it would be a complete 

 nucleated organic cell. Endamoeba may be recommended as a 

 convenient illustration of a primitive form of the organic cell, on 

 account of its comparatively ready accessibility. — Proc. Acad. Nat. 

 Sci. Philad., October 7, 1879. 



On the Habits and Parthenogenesis of the Halicti. 

 By M. J. H. Fabees. 



Two species have chiefly furnished the materials for the prepa- 

 ration of this paper, namely Halictus lineolatus, Lep., and H. sex- 

 cinctus, Latr. The investigation of the former was made under the 

 most favourable conditions; every day, at whatever moment he 

 chose, and from one end of the year to the other, the observer had 

 under his eyes the object of his inquiries in its natural state of 

 being. The place of observation was in front of his door, in the 

 open country, in the midst of meadows. It was among the osier- 

 beds of the alluvial deposits of the Aygues, a torrent to the north of 

 Orange, that the second species (H. sexcinctus) was observed, in a 

 colony sufficiently populous to lend itself to detailed observations. 

 Followed up for a whole year, the study of these Hjmenoptera has 

 furnished the following results. 



Among the Halicti there is no society in the entomological sense 

 of the word : the family is not common ; and the cares of all have 

 not in view the interests of all. Each mother is only preoccupied 

 with her own oviposition, and constructs cells and collects pollen 

 only for her own larvae, without interfering at all with the rearing 

 of the larvae of others ; but there is nevertheless cooperation between 

 them for general work, of which several may take advantage with- 

 out hampering each other. This common work is the gallery, which, 

 ramifying in the depths of the soil, gives access to various groups 

 of cells, each of which groups is the property of a single Halictus. 



