234 EEV. T. E. E. STEBBING ON THE 



The first antennee have the first two joints rather robust, the second rather shorter 

 than the first, the two together little longer than the narrower third, which is rather 

 longer than the five-jointed flagellum. In the second antennae the last two joints of 

 the peduncle are equal, neither as long as the seven-jointed flagellum. 



The mandibles are similar in type to those of the preceding species, but with 

 broader connexion between the blade and the peduncle. The maxillipeds have the 

 second joint broad in proportion to its length, the produced plate rather large, with 

 only one coupling-spine, the third joint rather large, and the sixth shorter than the 

 fifth, instead of longer as it is in the preceding species and the next. Adjacent to 

 the base of the maxilliped there is a plate, with a small apparently movable joint 

 at the apex, which may possibly represent a second maxilla. 



The first gnathopod shows only three joints, of which the apical is minute, supported 

 by a joint of very moderate size, resting on an opercular joint of vast expansion, which 

 has the upper part of its convex margin fringed with setse. The second gnathopod is 

 leg-like, agreeing in general proportions with the first perseopod, but, as the figures 

 show, less spiky, and with the fourth joint bulging inward, whereas in the pereeopod 

 that joint is dilated distally outward and has spikes on its inner margin. The second 

 perseopod has numerous spine-teeth on its long third, dilated fourth, and rather small 

 fifth joints. In the third pergeopod the spikes are very conspicuous on the fourth and 

 fifth joints. 



The pleopods have narrow branches, without fringing setse. No special masculine 

 appendage could be detected on any pair. 



The uropods have the branches shorter than the telsonic segment, the inner broader 

 but not longer than the outer, both carrying sette. 



Length of specimen 2'5 mm. 



The specific name is compounded of the Latin words schistos, divided, and frons, the 

 front, in allusion to the frontal excavation by which it is easily distinouished from 

 the nearly allied Norwegian species, Gnathia abi/ssorum G. O. Sars. 



Taken by the 'Porcupine' Expedition, 1869, from 208 fathoms, west of Mid 

 Ireland (Station 13, lat. 53° 42' N., long. 14° 11' W.). 



Gnathia sp. 



A specimen about 6 mm. long was taken by the ' Porcupine' Expedition in 1870 

 from 250 fathoms off" Vigo, Spain (Station 12). .As it is only in the "Praniza" sta^e, 

 it would be unadvisable to give it a specific name. It may be mentioned that the 

 telsonic segment is broadly tapering till quite near the end, when it no lon^-er tapers 

 and has the narrow apex sharply notched, carrying a single setule. The inner branch 

 of the uropod is broad. 



