GENERA AND SPECIES OF THE NEMERTEANS 



Sub-Order.— ENOPLA. 

 Proboscis furnished with stylets. 



Family I. — AmphiporidjE.* 



Sub-Family. — Amphiporin^:. 

 Proboscis proportionally large. 



Genus I. — Amphiporus. Ehrenberg, 1831. 



Before the time of Ehrenberg the species of this group had chiefly been included under the 

 genera Fasciola and Planaria. In his f Symbolse Physical/ published in 1831, this author 

 established three genera, viz., Polystemma, Ommatoplea, and Amphiporus, for the reception of 

 animals probably belonging to the present type ; and, while there is room for doubt with regard 

 to the exact nature of the first two genera, as illustrated respectively by the examples Polystemma 

 adriaticum and Ommatoplea tceniata, it is quite clear to every observer that his Amphiporus albi- 

 cans from the Red Sea is a characteristic representative of the Fnopla, closely allied to A. lacti- 

 Jloreus. I have therefore deemed it right to use for the typical forms that generic name about 

 which there can be no misunderstanding, and which name, moreover, is contemporaneous with 

 the others. Usage, perhaps, inclined me to favour the adoption of the generic title Ommatoplea, 

 but in the present state of our knowledge this nomenclature would not have been strictly appro- 

 priate, and by the discovery of the typical form from which Ehrenberg drew up his description it 

 might be our misfortune to find that it is one of the Anopla, since there is nothing decisive in his 

 account or figure. The name here adopted is not free from faults, for the Anopla as well as the 

 Enopla have a pore at either end ; but the term Ommatoplea stands in the same position, nume- 

 rous eyes occurring in the one group as often as in the other. In his description of the genus, 

 Ehrenberg, although noting and figuring the glandular papillae of the proboscis, omitted to observe 

 the stylets, and did not truly comprehend the situation and relations of the mouth, as he mistook 

 the proboscidian aperture for the latter. The name Polia instituted by Delle Chiaje, and 



1 'Aju^t and iropog, an aperture. 



