THE BLOOD-CORPUSCLES OF THE ANNELIDES. 481 



is the following 1 quotation from p. cxxix. of my ' Forms of Animal 

 Life,' published in 1870: — 



• In a few Annelids, again {Syllidea armata, the Opheliae, the Cirratulida, and the 

 Staurocephali and Branchiobdella), the so-called pseud-haemal system contains corpus- 

 culated blood, and communicates with the perivisceral cavity so as to form a lacunar 

 circulation.' 



In answer to Professor Lankester's attack I have to say, that a 

 careful consideration of the passage just quoted, and even as just 

 quoted — that is to say, isolated and apart both from the connection 

 in which it stands, and from discussions of the same subject else- 

 where in the same book — is sufficient to suggest to any unprejudiced 

 observer that the error which it contains is simply an error of the 

 press. The passage should run, as by a most trifling and obvious 

 transposition and alteration it can be made to run, thus : — 



' In a few Annelides, again {Syllidea armata, the Opheliae, the Cirratulida, and the 

 Staurocephali ), the so-called pseud-haemal system contains corpusculated 



blood, and in Branchiobdella communicates with the perivisceral cavity, so as to 

 form a lacunar circulation.' 



As regards the passage when thus altered, I shall hereafter 

 attempt to show that it states what is currently accepted as our 

 knowledge of the subject. But I have first to prove that, as it 

 stands in the book, it should have suggested to Professor Lankester 

 that it should be thus manipulated and altered. Taking then 

 the passage as it stands, and as isolated, I will ask the candid 

 reader to note the eleven words contained in brackets, and par- 

 ticularly the last five of them. He will observe that a comma is 

 placed after each of the three sets of words, 'Syllidea armata ,' 

 4 the Opheliae' 'the Cirratulida;' that to these three sets of 

 words, a fourth similar set is added in the words, 'and the 

 Staurocephali? to which no comma is appended ; and finally, that 

 to this fourth set of words, denoting a fourth set of Annelides, 

 a fifth set is added in the awkward set of words, 'and Branchi- 

 obdella? Surely the clumsy repetition of the particle ' and ' might 

 have been considered to indicate that something was wrong in the 

 sentence, and when combined with the fact that no comma is 

 placed after ' Staurocephali? must show that this latter word had 

 somehow or other got dissevered from the terminal comma-super- 

 seding bracket, by an accidental intercalation into the space left 

 vacant above of the words ' and Branchiobdella? These two words 

 should be slightly altered into ' in Branchiobdella : ' and secondly 



1 i 



