40 Ins. 
COLEOPTERA. 
inner face of elytra ; terminal portion of epipleura narrow ; humeral 
area of elytra not limited behind by a raised line. To include about 50 
species ; among those previously known (most of which were described 
under Hydropoius ), the following are figured : — bicostatus , Schaum, cari- 
natus , Aub6, and striatellus , Lee., pis. xii. fig. 152, xiii. figs. 154 & 155 ; 
add D. longipes , Persia , planicollis, Asia Minor, p. 420, dories , Caucasus, 
p. 421, scutellaris , Cyprus, p. 42G, amurensis , Irkutsk [!], p. 427, prin- 
ceps y Sinai, p. 428, seriatus , Hedjaz, arabicus , Jeddah, p. 429, islamiticus, 
Kurdistan, suavis , Greece, p. 430, indicus , N. India, abyssinicus, pi. xii. 
fig. 153, Abyssinia, p. 431, suffusus and prosternalis , N. America, p. 434, 
spp. nn. ; add D. opaculis , sp. n., id. Biol. Centr. Am. Col. i. (2) p. 27, 
Mexico. 
Mcthles , id. 1. c. pp. 489 & 873. Placed after Celina ; scutellum con- 
cealed, base of thorax acuminate and produced in the middle, front and 
middle tarsi five-jointed, sub-cylindrical, basal joints not dilated, nor 
clothed beneath, third joint not bilobed ; swimming legs feeble ; ex- 
tremity of body spinose. To include M. spinosus, Egypt, p. 489, rectus , 
Mesopotamia, and punctipennis, pi. xiii. fig. 162, p. 490, Lagos, Ashantee : 
spp. nn. 
Hydrotrupes , id. 1. c. pp. 492 & 875. Allied to Agabus ; labial palpi 
very short and stout ; their terminal joint subquadrate. Type, H. pal - 
palis, sp. n., 1. c. pi. xiii. fig. 163, California. 
MetronecteSy id. 1. c. pp. 492 & 875. Coxal lines and border almost 
absent ; antennas and palpi short and stout ; hind coxae but little deve- 
loped, short, the anterior border but little arched ; wings of metasternum 
large. Type, Agabus aubcei , Perris (figured, pi. xiii. fig. 164). 
Jlybiosoina , id. 1. c. pp. 537 & 886. Placed after Agabus ; hind coxae 
large, with greatly arched upper border, wings of the metasternum very 
slender, parallel-sided, but much curved, swimming legs short and stout, 
epipleurae narrow behind the middle. Type, Agabus regularis , Lee. 
(figured, pi. xiv. fig. 174). 
Platynectes, id. 1. c. pp. 538 & 887. Placed after Ily biosoma ; sides of 
prothorax with a raised margin, hind coxae very large ; wings of meta- 
sternum much reduced, slender and linear ; hind legs rather long and 
slender ; epipleurae very narrow behind the middle. To include Agabus 
reticulosus and latissimus, Clark, Dytiscus decempunctatus, Fabr. (figured, 
pi. xiv. fig. 175), A. dissimilis, Sharp, undecimpunctatus (figured, l. c. 
fig. 176), decemnotatus and nigerrimus, Aub£, various other known 
species ; P. cenesccns , p. 538, limbatus, Australia, obscurus, Tasmania, 
p. 539, dcemeliy Australia, p. 542, ornatifrons , Brazil, p. 544, and para- 
nanus, Parana, p. 545 : spp. nn. 
Leuronectes, id. 1. c. pp. 546 & 887. Placed after Platynectes ; sides of 
prothorax without raised margin ; coxal lines present. To include 
Colymbetes gaudichaudi , Lap. (figured, pi. xiv. fig. 177), probably Agabus 
muelleri , Kirsch, and L. parallelus, sp. n., I . c., Colombia. 
Agametrus, id. 1. c, pp. 547 & 888. Placed after Leuronectes ; side of 
prothorax without raised margin ; coxal lines absent. Types, Colymbetes 
peruvianus, Cast, (figured, pi. xv. fig. 178), and labratus and humilis , 
spp. nn., 1. c. p. 547, Venezuela. 
