> 



AJ. 



Ixxxiv 



777^ BEGINNINGS OF LIFE. 



freely. But Itzigsohn says :— ' If a number of these remain 

 conjoined, and move about with a rowing kind of movement, 

 their locomotion being governed by a common spontaneity, 

 they represent a Volvox-X\\^Q colony, which, perhaps, may 

 even have been described as Volvox by authors. The micro- 

 gonidia of the EuglencE, like those of all the Algse hitherto 

 examined by me, are the motile parent cells of extraordinarily 

 minute spiral filaments. They are at first green, gradually 

 becoming pellucid— exacdy like the " Spermatospheres " of 

 Spirogyra, presenting a monadiform aspect. A peculiar 

 appearance arises when many microgonidia, in such groups, 

 remain green whilst the others have already become clear as 

 water ; the mass then presents, in fact, the aspect of being 

 composed of two kinds of animalcules. Such or similar con- 



>"'' 



f^ 



Pr.G.Oro. 



'"' " • Klp size V 



#rp 



(hoses 



The) 



• , ,, such as one 



4 observation- 



the 

 T 



:Ois 



d ar 



jnde 



Of 



:,, though placed 

 '.ievelop into anim 



;&os says : 



\\'hcn 



sJajfrom the same 



; a certain fashion i' 



ditions would represent several species of the supposed genus ^]^ an adjacent 

 Uvella (afomus, glaucoma, Bo do, &c.). Each ultimately colour- 



Vv 



:esiilts, even though 



i 



less microgonidium, then, by the dissolution of its minute ,^^^ qQ ^^^^ xm-xzL 

 gelatinous envelope, discharges a small motile spiral filament. ^^^^^^^ j^ ^^ ^^^^ 



These spiral filaments do not seem to be destined for 

 the purposes of impregnation ; for they gradually increase in 

 length and thickness, soon exhibiting numerous spiral turns.' 

 They, in fact, exchange their Spir illa-X\\.Q for a Spirulina-ioxm- 

 'Fina'lly, when their motile faculty has become weakened, 

 they affix themselves by one extremity to any larger object 

 near (e.g. Conferva filaments, &c.), whilst the other extremity 

 continues to move about with a creeping motion— the pecu- 

 liar Oscillatorian movement, in performing which a young JDiena do occur 1 

 filament frequently returns to the spiral.^ The last described ^ chance to n^o 

 condition constitutes the Lepiothrix of authors. The fila- c,,l.. . i' 



: place generally w 

 ■»Bld not suspect thv 

 .% should certain 

 ''of change rather 

 ^''"^'^^tion, do they 



■'^"ttONvhichothci 



I know not 



-%iis \ 



\{ 



ments now gradually become thicker; and though at first ;Uc,, ^ccor^i^ ' 

 of the lightest emerald-green, they gradually assume a deeper li^. ^-^Z tO 

 and deeper tint. The first indications of articulation are j^j^j^^e placer- 

 perceptible in them, until at last a young Oscillatona is agam \^^^ ^ naiiiy of ^j 

 perfected.' ''^ of the 



1. 



Aiin. 



^es Sc. X 



