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the mouth of Balanoglossus. The subneural gland is almost certainly 

 functional in Cephalodiscus, being connected with food-ingestion, but 

 as the mode of feeding in Balanoglossus would appear to be of a diffe- 

 rent nature, it is probable that the subneural gland, if present at all, 

 would in this group be vestigial. Again, we know that there has been 

 a secondary pre-oral extension of the pharyngeal region in Entero- 

 pneustaso that it is possible that the subneural gland might in this 

 group be pushed further forward into the proboscis. Although in Bala- 

 noglossus it has atrophied I think it can be identified in Schizocardium, 

 Olandiceps and Spengelia, as the organ called the "vermiform process" 

 of the "Eicheldarm" referred to by Dr. Harmer as "the slender an- 

 terior portion of the notochord". Strangely enough, Willey has re- 

 cently expressed the same view and ascribes it to Dr. Harmer. If 

 this is the case, then I am in agreement with the latter on this point 

 but he must in this case have forsaken his first formula quoted above, 

 for "the whole is not equal to its part". Dr. Harmer recognised that 

 there was "no essential histological difference" between the subneural 

 gland of Cephalodiscus and the organ we refer to, but I fail to find 

 that he suggested anything further than that the latter was an inte- 

 gral part of the whole "Eicheldarm". Willey goes further, however, 

 and suggests that the so-called "notochord" of Cephalodiscus is homo- 

 logous with the vermiform process, or part of the "stomochord" of 

 Enteropneusta. I am inclined to go further still and regard the latter 

 as an organ distinct from, although organically connected with, the 

 notochord of Enteropneusta and would apply the term subneural 

 gland to it, when present in the members of this group. The detailed 

 prooffor this view I must leave at present, but might mention the objec- 

 tions I urged (No. 545 Zool. Anz.) to the comparison of the subneural 

 gland of Cephalodiscus with the whole "Eicheldarm" of Balano- 

 glossus do not apply to the comparison with the "vermiform process". 

 (3) With regard to Dr. H armor's third formula my views have 

 been expressed recently (Rep. Brit. Assoc. 1898), and to these I adhere. 

 Dr. Harmer objected to the name Diplochorda mainly because 

 '^Cephalodiscus affords no support" "to the theory of the originally 

 paired character of the notochord of Balanoglossus^^ . I now am incli- 

 ned to believe that this name will probably have to be used not only 

 for the three forms Cephalodiscus^ Phoronis and Rhahdopleura^ but to 

 include Enteropneusta as well. I find in the one or two Tornaria I 

 have been able to obtain that the pharynx has paired pleurochords 

 laterally. Whether they take any part later in the formation of the 

 stomochord or simply remain in s i t u as the dorsal branchial portion 

 of the pharynx, as in Cephalodiscus, is immaterial. They are paired 



