320 NATURAL SCIENCE. Oct.. 1893. 



Examination showed him that the septa in the upper half were four in number 

 instead of two. The following diagram represents the abnormal half as it was when 

 it reached Plymouth : — 



c-qs a'' c-c" a'' c c^ a 7 c-c'' A^ c-ci 



I V I V I I ■ I 7 I 



A Arms. c.c Colleto-cystophores. 



Mr. Garstang was good enough to preserve the specimen, and it is now at Plymouth, 

 so as to be available for anyone working there. 



My first impression was that the supernumerary arms arose by fission of the 

 normal ones (though it is difficult to account for the non-fission of arm "'). This was 

 also Mr. Garstang's opinion ; and though my rough notes state that the super- 

 numerary arms were, when first observed, smaller than the others, and arose as 

 outgrowths, the notes were made under such disadvantages that I willingly withdraw 

 them in favour of his view. 



Henry Scherren. 



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ERRATUM. 



Page 106. The lines under the heading " Abyssinian Sub-Region " should be 

 transferred to the heading " South African Sub-Region " below. 



