486 
PROTOZOA. 
Tlie developed protoplasmic filaments execute rapid undulatory 
movements in the intestine, similar to those of the Nematoid 
worms. (It is probably similar pseudofilaria of the Gregarinae 
of the earthworm which have been taken for young Nematoids.) 
The pseudofilarium subsequently ceases its movements, and de- 
velops a nucleolus by a process somewhat analogous to crystal- 
lization. The pseudofilarium continues to shorten; the layer of 
the nucleus becomes more sharply defined ; transparent zones 
form round the nucleolus; and we thus have a perfect young Grc- 
garina, which soon acquires the size and characters of the adult. 
The successive disappearance of the nucleoli is only to be ob- 
served in the adult ; in the young, the nucleus never encloses 
more than one large nucleolus, which generally contains a small 
vacuole. Van Beneden proposes the word to designate 
the substance of cytodes, and would restrict the term protoplasm 
to the substance of the body of a cell. The above observations 
are specially interesting, from the nucleolus and nucleus being 
developed on the cytode by endogenous formation. The course 
of development in the Gregarinidce is as follows; — (1) Monera 
stage, (2) Generative cytode stage, (3) Pseudofilarium stage, 
(4) Protoplast stage, (5) Encysted Gregarine stage, (6) Psoro- 
sperm stage. True conjugation does not appear to occur in these 
organisms; and their sometimes becoming attached is probably 
only an accidental phenomenon, analogous to the fusion of amoe- 
boid particles to form a plasmodium. 
A. Stuart has observed traces of a special digestive canal in Gregarinae^ 
Nadir. Ges. Getting. 1870, p. 102. 
Zygocystis pterotrachece, body-cavity of PterotracheUy and Monocystis tele- 
psaviy intestinal appendages of Telepsavus castorum, Odessa, spp. nn. Struc- 
ture &c. described by A. Stuart, Bull. P<5tersb. xv. pp. 497-602, plate. 
INFUSORIA. 
Giebbl very briefly notices the progress of knowledge on the Infusoria, Z. 
ges. Naturw. (2) iv. pp. 384 & 385. 
Euglena and Phacus, Tlieir various forms noticed by J. Barker & W. 
Archer, Q. J. Micr. Sci. xi. pp. 98 & 99. Phacus longicauda, triquetruj and 
pleuronectes are probably specifically identical, as are also E. geniculata and 
spirogyray and possibly P. tripteris : Archer, 1. e. 
Syncrypta volvox, Ehrenb. On its various stages, cf. W. Archer, 1. c. pp. . 
31G-318. He has observed it in a seemingly encysted condition. 
Aporea amhiguay Bailey. Archer (/. c. pp. 208-210) describes the “mo- 
nads” whose direct evolution and swimming away horn the summits of 
the branches he has observed. They appear to be closely allied to Monas 
consociata, Fres., recently placed by Cienkowski in his genus Phalansterium 
(probably =4porea, Bailey, which has the priority), along with a second 
species, P. intestimwiy Onk., only doubtfully distinct from the first. 
