THE GENERA OF NEMERTEANS. 



205 



The following table, analytically arranged, may be of 

 use in determining the genus of a given specimen: 



f very long and slender , often 

 I coiled together in knots; i)ro- 

 V boscis rather short 



Mouth before the' 



ganglia ; proboscis 



furnished with 



stylets ; body 



(HOPLONE- 



MERTINI) 



with four 





more or lessj 

 short and bul- 

 ky; proboscis/ 

 long ; head 



large eyes, body 

 short and stout 



small eyes, 



body more 



slender, very 



contractile 



viviparous 



oviparous 



with nume - 

 rous eyes , 



deep lateral 



fissure on both 



sides of the head 



(SCHIZONE- 



MERTINI) 



with one central stylet in 

 the proboscis 



with a curved hook in the 

 proboscis provided with 

 numerous small stylets 



body -margins bent upwards, the 

 frilled edges nearly meeting 



/ not so very long well develo- 

 in comparison! ped, furnished 

 to its width ; V with urtica- 

 eyes rarely nu- \ ling organs 

 gene- / 



body flat 



or roun-^ 



ded 



rally absent, 

 proboscis 



no stylets in 

 the proboscis ; 

 mouth be- 

 hind the 

 ganglia 



extremely 



long; eyes very 



numerous 



, attenuated, 

 i muscles of 

 f body wall very 

 \ strongly tinged 

 with red 



' no deep lateral 



Assures on the 



head (PALAE- 



ONEMER- 



TINI) 



posterior lobes of the 



ganglion present, 

 I coalesced with the 

 I supero-anterior lobe; 



no visible posterior 

 lobe to the ganglia 



no eyes, opening for 

 the proboscis dis- 

 tant from the tip of 

 the snout 



eyes, opening for 

 the proboscis ter- 

 minal 



head pointed, con- 

 tinuous with the 

 body 



head distinct from 



the body, spathuli- 



form 



Nemertes. 

 Oerstedia. 

 Prosorhochmus. 



Tetrastemma. 



Amphiporus. 



Drepanophorus. 

 Langia. 



Cerehratulus. 



Borlasia. 

 Lineus. 



Valencinia. 

 Folia. 

 Cephalotrix. 

 Carinella. 



We now pass to the description of the species found at 

 Naples. Only a short notice will be given of those which have 

 been already satisfactorily described by Mac Intosh or 



Notes from the Leyden Museum. 



