96 EUROPEAN NEMERTEANS. 



secondary grooves are visible on eacli side, others being 

 situated laterally in the vicinity of the external opening 

 of the ciliated duct. On compression the brain was visi- 

 ble by transparency and appeared similarly shaped to that 

 of Carinella annulata: a simple thickening of the lateral 

 nerve-cords, ventrally united by a stout commissure. The 

 dorsal commissure was not visible under these circumstan- 

 ces, nor was there any trace of a third (posterior) pair 

 of lobes to the ganglion. 



Microscopic sections clearly proved this apparent resem- 

 blance with Carinella to be confirmed by the internal 

 organisation of the animal. As in that genus the lateral 

 nerve-trunks are situated quite exteriorly to the muscular 

 body-wall and so are the cerebral lobes. These latter are 

 only the enlarged anterior portions of the lateral trunks. 

 Histologically the nervous system closely agrees with that 

 of Carinella annulata. An important difference however 

 is situated in the ciliated canal, which commences at the 

 above mentioned lateral opening and penetrates into the 

 cerebral lobes, terminating in the midst of the nerve-cells. The 

 presence of this canal , the physiological and morphologi- 

 cal signification of which was fully discussed elsewhere ^) , 

 gives an unexpected importance to thifj species , which 

 henceforth must be regarded as intermediate between the 

 more primitive (Carinella) and the more developed genera 

 (Polia) of Falaeonemertini, the latter of which , by 

 certain aflinities distantly tend towards the highest diffe- 

 rentiated forms of Nemerteans, the Hoplonemertini. 



The colour of the specimen was red with a brownish 

 hue. It measured 3^, Cm. Under the microscope some 

 faint transverse interruptions of the uniform pigment were 

 visible, encircling the body. 



Still it can never be confounded with young specimens 

 of Carmella annulata , even on superficial inspection. 



Habitat: Capri. 



J) L. c. Verh. dcr Kon. Akademie, Amsterdam. 1880. 



Note* from the Ley den IMuseum, ^Vol. II. 



