ON THE ZOOLOGICAL STATION AT NAPLES. 



267 



6. Last thoracic segment produced into blunt angles, not spines. 



Outer branch of posterior antennae twice as long as inner, 

 endopodite of posterior foot-jaw only quarter as long as 

 second basal ; first basal of fourth foot almost naked=genus 

 Chirundina, Gbt. 

 One species — Ch. streetsii, Gbt. 



II. Last thoracic segments rounded, not produced info spines or angles. 



7. Head with or without a crest, outer rami of posterior antennae 



not twice as long as inner, exopodite of the maxilla small, 

 and its middle bristles the shortest. Endopodites of first 

 and second feet one-jointed=genus Undeuchceta, Gbt. 

 Two species—?/, major, Gbt., U. minor, Gbt. 



8. Rostrum sometimes absent. Outer rami of posterior antennre 



two to four times as long as inner. Head sometimes with a 

 crest. Endopodite of first and second feet one-jomted. 

 First basal of fourth foot armed with characteristic spines 

 =genus Euchirella, Gbt. ^ 



Species— Fic^e Giesbrecht u. Schmeil, ' Thierreich, p. 35. 



C. Head tvithout rostrum. 



9. Outer branches of posterior antennae and mandibles twice as 



long as inner ; endopodite of posterior foot-jaw not half the 

 length of second basal ; exopodite of maxilla with eight to 

 ten bristles ; exopodite of first foot with three segments, first 

 segment with bristle ; endopodite of first foot one-jointed, 

 of second one-jointed (trace of articulation); third and 

 fourth feet three or two jointed ; basals of fourth foot with 

 simple basis = genus Chiridius, Gbt. 

 Two species— CA. ^jop^jei, Gbt., Chiridius obtusifrons (fears). 

 10. Thorax ending in acute upturned lappets. Anterior antennae 

 shorter than thorax, densely bristled. Inner ramus of pos- 

 terior antenna more than twice the length of outer, and only 

 six-jointed. Posterior foot-jaws with sensory appendage on 

 first basal =genus Bryaxis, Sars. 

 One species — B. brevicornis, Sars. 



II. — A List of Naturalists who have worked at the Zoological Station 

 from the end of June 1901 to the end of June 1902. 



