100 Journal New York Entomological Society, t^'oi- xxix. 



Fig. 28. Mandible of Squilla sp. (Stomatopodan Crustacea). 



Fig. 29. Mandible of Caprella sp. (Amphipodan Crustacea). 



Fig. 30. Mandible of Calanus (Copepodan Crustacea), drawn partly from 

 specimen, partly from figure by Borradaile. 



Fig. 31. Left (?) "mandible" of Peripatus sp., drawn from several 

 sources. 



Fig. 32. Distal region of mandible of isopod crustacean, Cirolana con- 

 chaniiu. The mandibular palpus is cut off. 



Fig. 33- Mandible of ostracod crustacean. Acaufliocypris biciispis, from 

 figure by Claus. 



Fig. 34. Apical region of mandible of ostracod crustacean, Cypris pubcra, 

 from figure by Claus. 



Fig. 35. Mandible of Lcander serratus (Decapodan Crustacea). 



Fig. 36. Body of mandible of Ligia sp. (Isopodan Crustacea). 



REVISION OF THE GENUS LIGYROCORIS STAL 

 (HEMIPTERA, LYG^ID^). 



By H. G. Barber. 

 RosELLE Park, N. J. 



The genus Ligyrocoris was founded by Stal in 1872^ with Cimex 

 silvcstris L., Fiel). named as type. The author's short diagnosis trans- 

 lated reads: " Disk of the second and third ventral segments furnished 

 on both sides behind the acetabulse with a denuded, densely and very 

 delicately strigose vitta ; first segment of the posterior tarsus doubly 

 or in exotics more than doubly longer than the two apical segments 

 together ; anterior femora armed beneath anteriorly with two or three 

 larger and several very minute spines ; third segment of the rostrum 

 much longer than the fourth." 



In 1874- Stal in his treatment of the genus as it pertained to 

 America dropped from his diagnostic characters the relative lengths 

 of the third and fourth segments of the rostrum and of the segments 

 of the posterior tarsus. He arranged six species under the genus, as 

 follows: L. balteatits and nuiltispiiut'S as new species, Plociomenis 

 syh'cstris Lin., Plociomcra Uiigiosa Stal, Lygcrus abdouiinalis Guer. 



1 Stal, Of. Vet. Akad. Forli, XXIX. 51, 1872. 



2 Stal, Enum. Hem., I\', 144, 145, 1874. 



