676 MR J. T. CUNNINGHAM AND MR G. A. RAMAGE ON THE 



rapidly or more slowly. There is usually only one cilium to a cell, but 

 occasionally a cell is seen bearing two. These ciliatedcells vary much in size, 

 and the smaller ones are not spherical, but have an irregular outline. It is 

 evident that these smallest cells, which are quite transparent, are almost 

 entirely composed of unaltered protoplasm; even the smallest usually contain 

 a single minute concretion. In the ciliated cells of moderate size it is seen 

 that the substance containing the concretions is modified protoplasm, and it 

 forms a separate spherical mass surrounded by a delicate layer of protoplasm 

 which is continuous with the cilium. In the oldest and largest cells both 

 cilium and protoplasm have disappeared, and nothing is left but a thin-walled 

 vesicle containing a group of gelatinous globules, each with its concretionary 

 nodule at the centre. These vesicles easily break up, and thus the gelatinous 

 globules are scattered over the slide. The process of secretion then here 

 consists in the successive evolution of minute protoplasmic ciliated cells into 

 the large non-ciliated vesicles carrying concretions ; the vesicles drop off in 

 succession from the epithelium into the gland cavity, and so reach the exterior. 

 A similar mode of secretion can be made out in the nephridia of all Chaetopods, 

 and also of Mollusca. 



The ovaries in the female and testes in the male have similar positions and 

 relations. There are in each sex four gonads in two pairs, lying on either side of 

 the intestine. Each organ is a much elongated thick band or mass. In the 

 natural condition all four organs are rolled up with the loop of the intestine 

 into a smooth cylindrical mass, enclosed by a membrane. When the organs 

 are disentangled the elongated form of the gonads is seen, and it becomes 

 evident that they are free everywhere except at the anterior end, which is 

 attached to one of the metameric transverse vessels of the body-wall. A single 

 blood-vessel given off from the lateral vessel is seen running the whole length of 

 the organ, and supplying it with capillaries. No efferent vessel was to be seen. 

 The somites to which the gonads thus belong are the 7th and 8th setigerous. 

 The ovaries have a bright green colour ; the testes are pale yellow. The male 

 specimens, as far as our observations go, are larger than the female. We have 

 no clue as to the manner in which the generative products escape (PL XLVI. 

 fig. 39). 



Genus Flabelligera, Sars, 1829. 



The distinguishing characters of the genus Flabelligera are the presence of 

 a thick mucous sheath surrounding the body, and containing long, knobbed 

 epidermic processes, and the large number (circ. 40) of branchial filaments on 

 each side of the head. The usual single pair of ciliated tentacles are present, 

 ventral to the branchiae ; these are much thicker than the branchiae. The 

 bristles of the 1st setigerous somite only are directed anteriorly, and being long 



