6o 



lono- and strong spines on the inner margin. Fig. 21, Plate XIII shews eight spines and represents 

 the left foot. The first joint of the basiopodite of the right foot has seven spines. 



The fifth pair of feet is absent. 



Occurrence. - Two females were found in plankton collected with the Hensen vertical 

 net at Station 185, 1536 metres to surface. 



11. Euchirella ditbia nov. sp. Plate XIV, figs. 1 — 7. 



Female — length 7 mm. 



The cephalothorax is oblong ovate and moderately robust. The head is distinctly separated 

 from the first thoracic segment. It is without a crest but has a conspicuous rostrum. The apex 

 of the rostrum is faintly bifurcate. The fourth and fifth thoracic segments are completely separated. 

 The last thoracic segment is not produced, and is simply rounded off into the abdomen. 



The abdomen is composed of four segments. The combined length of the abdomen and 

 furca is distinctly less than one-fourth of the total length of the cephalothorax, from the frontal 

 margin to the base of the genital segment. The genital segment is slightly asymmetrical in 

 outline and is rather swollen below. It is nearly as long as broad at the widest part, and is 

 rather longer than the combined length of the next two segments. The second segment is 

 longer than the third. The third and fourth segments are of about equal length. The furcal 

 joints are about half as long as broad, and are as long as the anal segment. The posterior 

 dorso-lateral portions of the abdominal segments are clothed with fine short hairs. 



The antennules are twenty-four-jointed and extend to the end of the furca. 



The antennae, mandibles, maxillae, and maxillipedes are similar to those of Euchirella den fata. 



The exopodite of the first pair of feet is indistinctly three-jointed, and is furnished with 

 three outer-edge spines, as in the other species described above. 



The exopodite of the second pair of feet is three-jointed. The endopodite is distinctly 

 two-jointed. 



The third and fourth pairs of feet have a three-jointed exopodite and endopodite. The 

 first joint of the basiopodite of the fourth pair of feet, is furnished with a row of eight or ten 

 spines. Fig. 7, Plate XIV shews ten spines. The first joint of the basiopodite of the other foot 

 has eight spines. 



The fifth pair of feet is absent. 



Occurrence. Three females were found in plankton collected with the Hensen 



vertical net at Station 185, 1536 metres to surface. 



It is quite possible that one or more of the species now described as new, may turn out 

 to be identical with species obtained by Sars in the plankton collected by the Prince of Monaco, 

 but as only the preliminary descriptions without figures have yet appeared, I am unable to 

 determine whether this is so or not at present. 



Genus Undeuchaeta Giesbrecht, 1888. 



This genus is closely allied to Euchirella, but the females are distinguished from those 



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