32 



BULLETIN : MUSEUM OF COMPAEATIVE ZOOLOGY. 



In Carinomella the proboscis is provided with a bulb-like expan- 

 sion near its anterior end (PI. 5, figs. 47, 49). The organ is thus 

 divided into three chambers, as in the Hoplonemertea. 



In the Paleonemertea and in Taeniosoma the proboscis is pro- 

 vided with two very strong layers of muscles, while most of the 

 Lineidae have three such layers. In the Paleonemertea the outer 

 layer consists of longitudinal muscles, and the inner of circular fibers 



V-r-nic 



Fig. 9.— Carcinonemertes epialti. Horizontal section through anterior portion of 

 body, showing position and extent of proboscis ; ac, mc, pc, anterior, middle 

 and posterior chambers of proboscis respectively ; cff, cephalic glands ; i, intes- 

 tinal caecum. 



(PI. 12, fig. 80). In Taeniosoma the order is reversed, the outer 

 layer being circular and the inner longitudinal. In the Lineidae 

 there is an inner and an outer layer of longitudinal fibers with a cir- 

 cular layer between, just as in the muscular layers of the body walls. 

 In a number of species of the Lineidae {Lineus rubescens and X. 

 Jlavescens, for example) the inner longitudinal layer is largely or 

 completely wanting. 



