cxl GENERAL SUMMARY OF SCIENTIFIC AND 



liquid both outward and inward, carrying along particles of 

 food and dirt, and you have some idea of the general charac- 

 ter of a Gromia." Another form is allied to the curious Pe- 

 lomyxa described by Greef. The entire body, and even the 

 protoplasmic outstretched threads, bristle with innumerable 

 silicious spicules. This wonderful organism is called Deina- 

 mceba mirabilis. The wonder exists in the fact that such 

 evidences of active will-force, or energy, of such complicated 

 physiological processes as digestion and reproduction, can go 

 on in a simple mass of partly transparent jelly-like proto- 

 plasm, the animal representing a single cell, without organs, 

 unless it possess a nucleus, which Leidy w r as unable to dis- 

 cover. The wonderful properties of the substance w<e call 

 protoplasm are further shown in the studies of Dr. Biitschli, 

 of Kiel, on the organization and reproduction of the Infuso- 

 ria. Though the Infusoria proper are much more highly de- 

 veloped than many naturalists suppose, Biitschli denies that 

 they produce spermatozoids which fertilize the nucleus (ova- 

 ry), as asserted by Balbiani and Stein. He also believes that 

 lasso-cells, like those in Hydra and jelly-fish, are developed 

 in a certain infusorian (Polykrikos), though he believes that 

 the Infusoria represent a single cell. This latter point Haeck- 

 el has endeavored to prove in an elaborate paper, containing 

 also a revision of the classification of the Protozoa. How- 

 ever, it seems to make little difference whether these strange 

 Protozoa are many-celled or unicellular, as the processes of 

 life exhibited by them are due to the protoplasm. As ob- 

 served in last year's Record, histologists now recognize the 

 fact, to use the words of another, " that the phenomena of 

 life, whether exhibited in the building up of structure or in 

 the transformation of energy, are solely dependent on the life- 

 stuff protoplasm and that the corpuscular or cellular con- 

 dition of that life -stuff is a secondary accident." Several 

 new Infusoria have been described by Haeckel and others; 

 while the remains of several Rhizopods have been found in 

 the hot springs of the Azores. Ascending to the Rotifers, 

 Professor Leidy has experimented on the common Rotifer 

 found in the dirt adhering to the mosses in the crevices of 

 pavements in Philadelphia, in order to determine how far 

 they could be revivified after drying up. It appears that 

 the Rotifers and their associates become inactive in compar- 



