47 



Archeri. SYN. : Diplophrys Arckeri, Barker, H. 

 andL., Archer, Greeff, Schulze ; Acanthocystis spinifera (?) Greeff ; Cysto- 

 phrys oculea, Archer ; Elaorhanis cincta, Greeff. 



The only species ; not observed by Prof. Leidy in 

 the mature form. Diameter, 10// to 20// (Schulze). Those 

 observed by Prof. Leidy, and placed by him in this 

 group measured only 4/^ to 5//. They were trans- 

 parent and each contained a bright, cherry-red, oil-like 

 corpuscle. 



GENUS YI. ACTINOSPH^ERIUM. 



Body spherical or oval, composed of finely granular 

 protoplasm, enclosing a mass of delicate, polyhedral vesi- 

 cles or vacuoles occupied by a clearer, hyaline proto- 

 plasm. The outer one or two layers of vacuoles more or 

 less distinctly defined from the interior by greater size, 

 translucency, and apparently by the intervention of a 

 thicker film of granular protoplasm. Nuclei numerous 

 and imbedded in the latter beneath the peripheral vacu- 

 oles. Contractile vesicles two, commonly opposite, in 

 the peripheral layer. Rays numerous, tapering exten- 

 sions of the granular protoplasm, including an axis- 

 thread, which starts beneath the peripheral vacuole 

 layer. 



Actinosphcerium EicJiornii SYN. : Actinopfays EichoniH, 



Ehr., Pritchard, and others; Actinophrys sol, Kolliker ; Actinosphce- 

 liwn Eichomii, Stein, Greeff, H. and L., Schulze, Leidy. 



Body transparent, colorless, usually with a single pe- 

 ripheral layer of the large vacuoles, which are deeper 

 than broad ; or, in large and old individuals, sometimes 



