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34. Sphaeronella Munnopsidis n. sp. 



(PI. X, fig. 4 a— 4 d.) 



FEMALE. The only specimen found was torn and half empty; it was ab. 5 mm. 

 in length and a little shorter than broad. The head is veiy small and not separated from 

 the trunk at all ; frontal and lateral borders are altogether wanting, whereas the sub-median 

 skeleton is developed into a single, good-sized, solid plate, to which the maxillae and maxilli- 

 peds are articulated (fig. 4b). Antennul* rather short, not distinctly jointed, but the length 

 of the first joint is easily seen, as its distal anterior angle protrudes in the usual way and 

 is furnished with setae wliich, however, are short; the setae on the distal part of the 

 anteunulae are scarcely of medium length. Antennae are wanting. The mouth is good-sized 

 and the mouth-border broad. The principal branches of the maxillulas are pretty long, the 

 additional branch a little shortei-. The umxillae are good-sized; their basal joint smooth, 

 supplied with two rows of short, thick, blunt sets or small processes along the inner margin 

 of the skin that connects it with the second joint. Basal joint of the maxillipeds of medium 

 length; on the inner side of its distal half are two areas of extremely short hairs; second 

 joint of normal length, somewhat dilated towards its distal end, on the inner side of which 

 are seen some minute haiis; third joint short and clumsy; in the left maxilliped it has at 

 its distal inner angle a shoit and very broad, rounded spine which is furnished with 

 exceedingly short hairs; in the light maxilliped this spine is wanting, but the jdint is still 

 shorter and broader, and its inner margin is hairy; in the left maxilliped the fourth joint is 

 tolerably short and hairy along the rounded end, in the right maxilliped excessively short 

 and hairy along both margins. Sub-median skeleton quite naked. Trunk naked; trunk-legs 

 wanting. Genital area somewhat laiger than the part occupied by the mouth-appendages; 

 it consists of a transverse plate which is a little more than twice as broad as long, fairly 

 rectangular, but the outline is irregularly sinuate; properly speaking, tliis plate consists of 

 a moderately broad ring of thick yellow chitine surrounding a thinner light area, which, 

 however, is somewhat more solidly chitinised than the skin which surrounds the ring. The 

 genital apertures are situated comparatively far apart, each at one end of the thinner area 

 and on its posterior margin; their distance fiom each other somewhat exceeds the length of 

 each; their direction is almost rectangular to the longitudinal axis of the animal, so that 

 their muscles are turned nearly straight in advance parallel with the axis, and their hindmost 

 lip is strongly curved. Somewhat in front of each genital aperture we see at the posterior 

 margin of the foremost transverse list of the frame a circular hole (k), which is no doubt 

 the orifice of a gland wliich otherwise I have been able to detect only in Mysidion ahys- 

 sorum and in Aspidoecia. Only one of the receptacula seminis (r) is shown in the drawing, 

 but to the orifice of each receptaculum is fixed a spermatophore, one of wliich (s) is well 

 preserved, whereas of the other (s') only the stalk is left. These orifices are situated 



