1 ProL . 
PROTOZOA. 
BY 
Stuart 0. Ridley, B.A., F.L.S. 
The General Subject. 
L. K. SCHMARDA, in his “ Zoologie” (2nd. edn., vol. i., Wien : 1877), 
classifies Protozoa on the following outlines: — 
Class i. Rhizopoda. 
Order 1. Athalamia or R. nuda (Fams. Amcebida^ Acinetida). 
Order 2. Rhizopoda imperforata (Fams. Psammamoebida, Gromiida, 
Cornuspiriday Arcelliday Miliolida'). 
Order 3. Foraminifera (Fam. Orbuliniday &c.). 
Class ii. POLYCISTINA. 
Order 1. Radiolaria monozoa (Fams. Thalassicolliday Actinophry- 
iday &c. 
Order 2. Radiolaria polyzoa (Fams. Sphcsrozoiday Colloaphcarida). 
Class iii. Gregarinoidea (Fams. Monocystiday Gregariniday Didymo- 
phyiday Acanihophora'). 
Class, iv. Infusoria. 
Order 1. Cymozoida (Fam. Vibrionida). 
Order 2. Mastigophora (Fams. Volvociday Astasiida, Dinobryiday 
PhacidUy Monadinay Cryptomonadinay Peridiniida, Noctilucida). 
Order 3. Peritricha (Fams. Vorticelliday Trichodiniday Ophrydiiday 
Ophryoscolecida ) . 
Order 4. Holotricha (Fams. Cyclidinay Enchelyiday Colepiday Tra- 
cheliday Ophryocerciday Colpodidd), 
Order 6 . Heterotricha (Fams. Bursariiday Stentoriday Tintinnidd). 
Order 6. Hypotricha (Fams. Oxytrichiday Euplotiday Aspidiscidd). 
G. VON Hayek, ‘^Handbuch der Zoologie,” (vol. i. Wien: 1877), 
classifies Protozoa as follows : — 
I. Animals living colonially round a skeleton of horn, silica, or car- 
bonate of lime traversed by canals opening on the surface. — 
Class iv. Spongidos. 
