of the Fishery Board for Scotland. 475 



Sarsiella (I) capsida, Norman. PI. xxv., figs. 27-32, 



Three specimens of an Ostracod — a Sarsiella — were obtained in some 

 sand collected about twenty-two miles to the north of the Shetland 

 Islands on May 17th, 1901. The sand had been for a time immersed in 

 formaline, and this may probably be the reason why the shells of these 

 specimens are comparatively soft and, when seen from the side (fig. 27), 

 show a somewhat even surface instead of being solid, and with the 

 surface more or less corrugated as seen in typical specimens (see Part IT. 

 of jNIonograph published by Professor G. S. Brady and the Rev. 

 A. M. Norman*). 



The specimen represented by the drawing (fig. 27) is that of a 

 female, and the shell when seen from the side is somewhat obliquely rotun- 

 date, the length being rather greater than the height, and measuring about 

 1*2 mm. by "9 mm. respectively ; the produced posterior projection is finely 

 ciliated, the ventral margin is also fringed with delicate hairs. The 

 posterior end is slightly compressed and bounded by an indistinct ridge 

 which extends obliquely across from the dorsal to the ventral margins. 

 The surface of the shell is not rugose as in the typical Sarsiella capsida, 

 ])ut is ornamented with numerous minute pits. 



In the dorsal view of the shell given in figure 28, the valves are open to 

 some extent on the ventral aspect ; this was due to the soft structure of 

 the shell (the shell could not be mounted dry in the usual way, but had to 

 be kept in water under a cover-glass while being figured). 



The various appendages of the contained animal resemble the drawings 

 given in the Monograph by Brady and Norman already referred to. 



The secondary appendages of the antennae are rudimentary. Each 

 consists of a rounded tubercle bearing two small spiniferous setfe (fig. 30a). 

 The caudal lamina is provided with six spines on the one side, but only 

 five on the other ; on this side there is no trace of a sixth spine, nor any 

 indication that a sixth had been present but had been broken off. 



In this specimen two ova were observed. 



The shell of the male differed little, if at all, from that of the female, 

 except that it was slightly smaller. The appendages also appeared to be 

 similar, except that the secondary branches of the antennte were, as in 

 closely allied species, more developed and fitted for grasping, and that the 

 caudal lamina was only provided with five spines on both sides. 



The first joint of the autennules in the male is rather longer than the 

 next, and the second, third, and fourth joints gradually decrease in 

 length, the fifth joint is almost obsolete, so much so that it is difficult to 

 make out whether there is really a fifth joint or not. There are no 

 setse on the first joint ; the second joint is furnished with a small seta 

 near the middle of the upper margin, and another on its lower and its 

 upper distal angles ; the third joint bears one seta on the upper and two 

 on the lower distal angles, while the fourth and (1) fifth joints carry 

 several terminal setje as shown in the drawing (fig. 29) ; some of these 

 hairs have an annulated structure, but this is not shown in the drawing. 



The antennae of the male are provided with a number of long 

 plumose sette, and the secondary branches, though somewhat rudimentary 

 (fig. 30), are moderately elongated and are apparently four-jointed — the 

 two middle joints being very small ; there is also a minute terminal 

 appendage. 



The first maxillae (fig. 31) are similar to those of the female in structure 

 and armature. 



* A Monograph of the Marine and Fresh-water Ostracoda of the North Atlantic and of 

 North-western Europe, Part II., Sci. Trans. Roy. Dublin Soc, vol. v, ser. ii. (January, 

 1896), p. 677, pi. Ix., figs. 1-4, 18. 



