Archer — On Freshtvater RMzopoda. 
83 
sarc, with a hyaline ectosarc universally surrounding the former. 
But upon closer examination it is seen that this external layer repre- 
sents a completely independent margin or border, ('Saum') with an 
outline of its own both outwardly and inwardly, and which equally 
surrounds the body proper of the rhizopod. All round the circumfe- 
rence can be seen the limits of this border Saum') in apposition to the 
surface of the inner body-mass Still more clearly can this be 
seen when the outer investment is burst by compression, and some of 
the sarcode mass ejected 
''Upon the application of re-agents, the distinction of this outer coat, 
(' Hiille') as a special and an independent part of the structure from the 
inner body, becomes even more decidedly expressed. Under acetic acid, 
whilst the body-mass loses its pigment, collapses, ejects the granules, and 
shows every indication of coagulation, the outer hyaline ' capsule' 
(' Kapsel') remains quite intact, and this even though the acid be 
allowed to act in a more concentrated condition, or for a longer time. 
The same thing takes place under dilute sulphuric acid, whilst on 
this being applied in a more concentrated form, the capsule wholly, and 
the contents partially, become dissolved. However, during the dis- 
solution of the capsule no other alteration takes place, that is, no 
sign of coagulation or the like Under the action of alkalies 
this capsule shows at first a tolerably persistent resistance, afterwards, 
however, becoming dissolved, without, however, having become pre- 
viously altered in appearance. The action of iodine is remarkable : so 
soon as this, in a dilute form, is applied, the violet colour becomes de- 
stroyed, and its place is taken by an at first clear yellow colouring 
of the whole of the contents, which gradually, under prolonged action, 
passes over into a deep blackish-brown, all which time the outer 
border maintains perfectly its colourless hyaline appearance, and 
only when penetrated at all sides by the iodine does it acquire a 
slightly yellow appearance, which, however, upon its being removed by 
blotting paper and water added, again disappears. Only under per- 
sistent action (of the iodine) does the capsule become tinged a light 
yellow, retaining, however, its pellucid glassy appearance. 
'' Erom all this" (urges the author) ''it follows that, as regards the 
problematic hyaline outer border in Amphizonella, it is not a proto- 
plasma-layer appertaining to the rhizopod body, but that we have really 
to do with a comparatively thick ' capsule,' bounded off and essentially 
distinct therefrom. 
' ' As regards the body-mass included by this capsule" (the author goes 
on to say), " this is permeated by a mostly dark-violet pigment ; fre- 
quently, however, it assumes a trace of yellow or brown; and this 
again depends upon a second j^igment diffusely distributed in the body, 
which, under circumstances hereafter to be mentioned, sometimes 
presents itself exteriorly. Under natural conditions, and without 
pressure on the covering- glass, little can mostly be made out as to the 
contents, owing to the darkness of the colour, with the exception of the 
vacuoles always existent in considerable numbers, though minute, as well 
