772 On Aquatic Carnivorous Coleoptera or Dytiscide. 
1280, Cybister marginicollis, Boh., Ins. Caff. I, p. 235. South Africa. 
“ Ovalis, depressiusculus, postice magis dilatatus, ad apicem nonnihil rotundatus ; nitidus, supra 
atro-ceruleus, subtus nigro-piceus ; antennis, labro, epistomate pedibusque luteis ; prothorace anguste 
luteo-marginato, dorso subtilissime, longitudinaliter aciculato, lateribus confertim punctulato ; elytris 
triseriatim punctatis ; margine inflexo ferrugineo. Long. 17, lat. 10 m.m. Hab., ad portum natalense.” 
[A description, l.c., follows this diagnosis}. 
It is probable that the species is closely allied to Cybister filicornis (No. 1129).—D. S. 
1281. Cybister olivieri, Crotch, Tr. Am. Ent. Soc. IV, p. 399. North America. 
“Very near C. fimbriolatus but smaller, with the thoracic and elytral margin narrower, the elytral 
vitta leaves the margin gradually, and is attenuated at about three-fourths. LL. 1-10 inch.” 
“ Mas, stridulating plate with three ruge. em., elytra smooth.” 
“ Florida.” 
According to a female recently communicated by Dr. Leconte to me, this does not belong to Megadytes, 
but is a Cybister unknown to me, and of very doubtful position.—D. 8. 
1282. Cybister prosternoviridis, Orm. Rev. Zool., 1843, p. 331. South America. 
“ Ovalis, convexus, postice dilatatus, ad apicem rotundatus et depressiusculus, nitidus, supra olivaceus, 
infra niger. Labro ferrugineo, thoracis lateribus viridis, in elytrorum margine viridis, prosternum 
viridis, pedibus anticis nigro-piceis, posticis nigris. Mas, elytris levibus. Femina. L. 365 1., 20 
mill. 
‘ T] habite le Brésil ?” 
No comparison with any other species is made, and as the locality is doubtful, the species will not 
easily be identified. I do not think it would be really from Brazil, and should suspect an African 
species may be intended.—D. 8. 
1283. Cybister vulneratus, Klug, Symb. phys. IV, pl. 33., f. 1 (the letter-press is not numbered). 
Arabia. 
“< Oybister niger, thorace lateribus, elytris (in mare levibus, remote punctato-striatis, in femina dense 
aciculatis) macula postica sanguineis. Long. lin. 12, Habitat in Arabia deserta.” 
“Statura fere D. immarginati, Fab. at angustior ac dimidio fere minor. Obscurus, niger. Caput 
obsolete rugosum, subalutaceum, ore antennisque testaceis. Thorax subrugosus, subalutaceus (in femina 
aciculatus) antice late sinuatus, postice obsolete bisinuatus angulis productis, lateribus obliqnis, vix 
rotundatis, parum reflexis, late obscure sanguineis. Pectus abdomenque levia. Abdominis segmenta 
intermedia puncto utrinque sanguineo. Segmentum ultimum apice obscure sanguineum. Pedes : 
Trochanteres anteriores toti, postica apice ferruginei. Femora anteriora apice lete ferruginea postica 
obscure sanguinea. Tibi anteriores (in mare cum tarsis) rufo-testacew, intermediz extus sanguine. 
Tarsi postici dense ferrugineo-ciliati. Elytra thorace plus quadruplo longiora, ante apicem parum 
dilatata, lateribus marginata, in mare levia, in femina dense aciculata, lineis punctorum impressorum 
ad basin approximatorum tunc remotorum tribus instructa maculaque pone apicem ad marginem externum 
elongata sanguinea ornata.” 
I think this is probably one of the forms of Cybister binotatus, Klug. (No. 1133.)—D. 8. 
1284, Cymatopterus obscuratus, Mann., Bull. Mosc., 1853, III, p. 154. Russian North America. 
“ Oblongo-ovatus, ultra medium valde ampliatus, posterius modice attenuatus ; supra nigro-fuscus, 
subtus cum pedibus aterrimus: labro, frontis margine antico late bisinuato, maculis binis obsoletissimis 
