42 W. C. Minor upon Fission in some Annelids. 
difference, like that be tween metagenetic and monogenetic fis- 
sions. I may add that I have not been able to discover that the 
point of its occurrence bears any relation to the number of buds 
already given off.9 
he sum of the preceding observations tends to show, that 
the “renewal of fission” has some special thaw that bins 
wider enquiry as to its true nature; that the two form fis- 
sah already known as “ parting” and ‘ budding” both a in 
the Naids, and ogeur so as to prove their morphologic and physi- 
ologic identity ; ; that “parting” appears to characterize the Naids 
with a prolonged upper-lip—the — a ta, While “budding” 
appears to characterize those with a short one—Nai ats, Dero, En- 
chytreeus, and wn sonceding to ‘ieee that the bud pro- 
duced by both these processes is identical with the parent; that 
as the bnds are here, so far as I know, sagt with their pa- 
rents in function and structure, there is no metagenetic fission ; 
and that therefore fission in these Naids, haven’ by “ parting” 
or by “budding,” is correlative to genesis in the great function 
of maintenance of the species, aud not a mere step in the his 
tory of the individual.'° 
It t may be worth while to refer briefly here to the power of 
reproduction from injuries commonly attributed to these little 
beings, especially as Dr. Williams, in his Report on the Britis 
Annelida, (Rep. Brit. Ass. Adv. Sei., 1851, p. 247), after quoting a 
summary of Bonnet’s well known experiments, says: ‘‘On the 
authority of hundreds of observations, laboriously repeated at 
every season, the author of this report can declare with deliber- 
ate firmness, that there is not one word of truth in the a 
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contradicting the statements so often repeated upon this subject; 
and I cannot doubt that his experiments have uniformly failed. 
re some a. differences to be considered in a future paper upon the 
histologic viata of fiss 
10 « From the peed of the two species, Arenicola and Nais, on which the au 
thor’s observations have been “hicfly conducted, the conclusion may be deduced that 
the ‘fission of the body’ in every othe nae gerne Anaelida in whieh it Son has for 
object in like manner to protect and incubate the ova,” “It becomes the last 
act of the —— worm, since the spel ns into which the ‘body i is sub-divided by 
yao e food.” “Tt is a catastre A ay ae whi ch Food autumn involves 
the ecureips ae mat Williams, "R Brit. Annel., pp. 2 
1 should be far rd wishing to pieces the foie 1sions I sot all other 
Annelids by mere analogy, but my observations are, at least, wholly sneneapatlill 
with a general application of Dr. Williams's tater to the Naids. 
The exact circle of life and its duration, I have not Ente nor do T feel cer 
tain that ped of the general gern at Leidy. Flora and Fauna within living 
; ia fossularis, and Willia - at large—are absolutely correct. For 
