VI 9S Carl Zimmer. 



in a stroiig spiiR', beyoiul vvliicli the apcx of tlic scale is not prciciiiccd; iio spiiie 

 Oll llie basal Joint. 



Mouth-parts fLindanieiitaily as in the geiius Aniblyops. 



First and second thoracic h'mbs likewise agreeing- with tiiose of the genus 

 Amblyops, except that tlie second Unib is coniparatively longer. 



Reniaining thoracic limbs broken away. 



Exopods of all the thoracic limbs with tlie outer distal corner of the basal 

 Joint slightly acuniinate; flagclliforni part well developed and composed of about 

 seventeen joints. 



hicubatory laniclls of the fcniale, two pairs. 



Pleopods in tlie only male, which is immature, liave the inner brancli of 

 the first pair already more developed than in D. dactylops and arnietl with niany 

 more seta-; otherwise they conforni to the Amblyops type. 



Telson coniparatively short; about two tliirds (slightly less) of the length of 

 the last Segment of the pleoii; snbtriangular in sliape; one and a half times as 

 long as broad at its base; margins tapering evenly to a bluntly rounded apex; the 

 distal third of its margins armed on eacli side with ten ratlier stout spines in- 

 creasing slightly in length tovvards the apex; a pair of median phimose sets situated 

 at the apex between the terminal spines of the margins. 



Uropods moderately slender: inner, one and two-thirds of the length of the 

 telson, apparently without spines on its inner niargin; outer, twice the length of 

 the telson. 



Length of a mature fcniale 16 mm, of an immature feniale 14 mm, and of 

 an immature male 15 mm." (I. c.) 



Verbreitung: Bisher nur aus den irischen Gewässern (750— SOü F. 

 Tiefe) bekannt. 



57. Dactylerythrops gracilura Tattersall. 



1907. Dactylerythrops gracilura Tattersall, Ann. nat. hist. ser. 7 v. 19, 



p. 111 — 112. 



„Carapace covering all the thoracic segments; broadly and evenly rounded 

 in front, without any trace of a rostral projection; antero-lateral corners rounded; 

 emarginate on its posterior border. 



Pleon a little longer than the carapace: first segment a little shorter than 

 the second, which is subequal to the third and fourtli; fifth segment slightly longer 

 than the fourth; sixth segment one and a half times as long as the fifth. 



Eyes very sniall, almost entirely covered by the carapace; very tliin and 

 menibranous; united at their bases by a membranous integument; outer distal 

 corners produced into a very acute fairly long flexible precess; a shorter and less 

 acute process on the inner corner; visual Clements very imperfectly developed, 

 confined to a small deeply-seated inass at the base of the outer process; no pig- 

 ment observed in preserved specimens. 



