32 



THE APODID^ 



PART I 



those already given in the foregoing pages, will be 

 gradually gathered as we proceed, for we shall find it 

 necessary to return to the subject again and again in 

 the course of the following discussion. 



A comparison of a limb of Apus with an Anne- 

 lidan parapodium such as is shown in Fig. 6 A,^ is 

 sufficient to enable us to homologise the shaft and its 



Fig. 6. — Diagram to compare an Annelid parapodium (.4)1 with a limb of Apus (B). 

 £■, gill; Cj, sensory cirrus of the dorsal parapodium ; t-j, ditto of the ventral para- 

 podium ; z>, ventral parapodium ; e, sensory endites. In all the figures the same 

 letters are used for the homologous parts. 



appendages with the dorsal parapodium, the claw 

 being the true tip. 



The gnathobase is the ventral parapodium. The 

 position of the gill is the same in both, and the 

 flabellum of Apus is clearly homologous with the 



^ Figure A agrees fairly well with that given by Ehlers as the para- 

 podium of a young Nereis ; we have added the gill, and the sensory 

 eirrusofthe ventral parapodium. See Taf xxi. 3 in ''Die Borsten- 

 wlirmer," Leipzig, 1864-68. 



