studies on marine Ostracods 485 



joint is very sparsely furnished with short hairs both on the anterior and the posterior sides; 

 along the distal boundary of the last-mentioned joint there is on the outside a series of short. 

 stiff hairs, often somewhat longer than the other hairs. 



Second antenna: — Distally on the inside close to the exopodite the p r o t o- 

 p o d i t e has a very short bristle. The exopodite has four bristles on the end joint. 

 The fourth to the ninth joints (on the Naples specimen the third to the ninth joints) of this 

 branch have basal spines, which decrease in size and strength the more proximally they 

 are situated, the one on the fourth joint being scarcely perceptible. The endopodite 

 (fig. 5) is small with scarcely distinguishable joints; its end bristle is about twice the 

 length of the stem. 



Mandible: — Protopodite: — Coxale: The scythe-shaped process (fig. 7): 

 The part situated distally of the main spine grows uniformly and gently narrower into a fine 

 point; its ventral edge is even and somewhat convex. The distance from the point of the process 

 to the main spine is about as great as the distance from the latter to the proximal ventral spine. 

 The dorsal bristle is attached somewhat nearer the point of the process than its distance from the 

 main spine and is situated somewhat more than half its length distally of the latter; it extends 

 to a distance of not quite half its length beyond the distal point of the process. The dorsal 

 serrate teeth are exceedingly small; they seem sometimes practically even to be absent; they are 

 not indicated in the figure. The main spine is rather small. There are four or five ventral spines, 

 the proximal one of which is rather strong, the rest are very weakly developed. On the part 

 situated distally of the main spine there are about eight or nine transverse rows of hairs. The 

 rod-shaped process is blunt distally and is there furnished with three short, fine, bristle-like 

 points. Basale: The backwards pointing process has three or four distal bristles, four triaena 

 bristles and one dwarf bristle. The triaena bristles have from one to six pairs of secondary 

 spines under the distal pair of spines. The peg on which the glands emerge is rather small. 

 The dorsal side of this joint is quite smooth, without either hairs or bristles. The exo- 

 podite (fig. 6) is, if we include its two distal bristles, about as long as or slightly 

 longer or shorter than the anterior side of the first endopodite joint. Endopodite 

 (fig. 6): Of the three ventral bristles on the first joint the shortest one has short hairs, the 

 two others have, proximally of the long secondary bristles, respectively about six to nine 

 and ten to sixteen pairs of short secondary bristles. Antero-distaUy this joint is not armed 

 with chitinous spines. Second joint: This has only one proximal bristle, which is about 

 a fifth of the length of the main bristle a. Between the main bristles b and c there 

 is a long, narrow bristle with short hairs. Tlie medial cleaning bristles are relatively few; 

 the specimen from the coast of England that I was able to investigate showed the following 

 arrangement of these bristles: 



„. , ^ ,., , ( .") bristles in a distinct lower row. 



Kight mandible , , , • , ■ , , 



\ '2 ,, below the mam bristle b. 



Lvh mandibk 



fi bristles in a distinct lower row. 

 •2 ., below the main bristle b. 



