FRESHWATER RHIZOPODS AND HELIOZOA. 329 
largest forms observed were from Wrynose, Lancashire. Length 
of shell 65 »; diameter of shell 54 p. 
Var. FIsstRostRA.—Sphenoderia fissirostris, Penard, in Mém, 
Soc. Phys. et d’Hist. Nat. Genéve, tom. xxxi. no. 2, 1890, p. 184, 
t. x. ff. 30-40. 
Body of shell elliptic-ovoid ; plates near the fundus round, but 
larger and elliptical towards the mouth. Length of shell 46 p ; 
breadth 23 4; diameter of mouth 13°5 ». Llyn Bochlwyd, 
N. Wales. Orkney Is. 
The only difference between this form and typical Sphenoderia 
lenta is the presence of the larger, elliptical plates near the mouth, 
and this is insufficient as a specific distinction. 
The genus Sphenoderia is not recognized by Blochmann (Die 
mikr. Thierwelt des Siisswass., I. Protozoa, Hamburg, 1895, p. 18), 
who merges it with the genus Huglypha. Personally, I think 
the narrow chitinous mouth, which is quite devoid of the plates 
of which the remainder of the shell is composed, is a very good 
generic character, and one which at once distinguishes Spheno- 
deria from Euglypha. 
Gen. Assutina, Hhrenb. 
45. ASSULINA SEMINULUM, Hhrenb. 1871; Leidy, Freshw. 
Rhiz. N. Amer. 1879, p. 225, t. xxxvii. ff. 15-27.—Difflugia semi- 
nulum, Hhrenb. Monatsh. Akad. Wiss. 1848, p. 379. Euglypha 
brunnea, Leidy, 1874. LE. tineta, Archer, 1875. 
General amongst Sphagnum and on wet rocks. Up to 3500 ft. 
on Lochnagar, Scotland. Orkney Is. 
Gen. Trinema, Dwardin. 
46. TRINEMA ENCHELYS, Letdy, in Proc. Acad. Nat.Sci. Philad. 
1878, p. 172; Freshw. Rhiz. N. Amer. 1879, p. 227, t. xxxix.— 
Difflugia enchelys, Hhrenb. Infus. 1838, p. 132, t.ix. f.4. Arcella 
hyalina, Hhrenb. Trinema acinus, Dujardin, Infusoires, 1841, 
p- 249, t.iv. f.1. Trinema complanatum, Penard. T. lineare, 
Penard. 
Probably the commonest and most widely distributed of 
testaceous Rhizopods, occurring abundantly in all kinds of damp 
and wet situations. The largest forms noticed were from 
Mickle Fell, N. Yorkshire, and it was observed up to 2700 ft. 
on Glyder Fawr, N. Wales. 
