Order. A E U H O P T E R A. LinnoeMs.
Famii.
(ÌF.NUS
C n . Sr
S y n .
.E S IIN A CLAVATA.
P la te 45. fig. 1.
L u !F.i .l u u d .e , Lea ch .
/E s n x .i. F a b r . Libellula p . L in n . Donov . C o rdulega stc r. L ea ch .
iE . abdonime rlav a to , basi gibbo ; corpore nigro, fusco viridique variegato. E x p an s,
alar. 3 i u nc .
« . with th e abdomen d a v a te gibbose a t th e base ; body b la ck , varied with broivn and
g r e e n ; stigma brown. E x p an se o f th e wings 31 inches.
iE slma d a v a ta , F a i r . E a t. S y s t. 11. p . 385. Spe c . In s . I . p . 526. 4.
Linnæus divides the dragon flies (Libellula, Linn) into two sections:— “ 1. alis paten-
tibus acquiesceiites and “ 2. (alis erectis) oculi distantes remotique.” Fabricius divides
the Linnæan Libellulæ into three distinct genera ; the first retains the Linnæan name,
the second and third are called Aeslma and Agrión. Their most essential characters
are taken from the form and situation o f the mouth, and therefore require a deep magnifier
to determine them with accuracy. Donovan states, that he had examined those parts in
the greater number o f the species Fabricius has described, and found Ins characters agree,
except m one instance ; which Donovan nevertheless considered a proof o f the impracticability
o f adopting the whole o f his system : he describes Chinensis, and refers
to the only figure that has been giv en o f it, in one o f the plates o f Edwards’s Natural
History o f Birds, 1745.* Had Fabricms ever seen and examined this rare species, he
must have referred it to his genus Agrión, each o f the lips being bifid, or two-cleft, as
in Libellula virgo and puella,— the essential characteristic o f the genus Agrión ; for the
months o f the Libellulæ o f Fabricius differ altogether in structure, and are not notched
in the slightest degree, as Libellula clavata, ferruginea, 6-maciilata, and the European
species, Libellula depressa, will sufficiently illustrate.
Donovan, however, rejecting the Fabrician generic distribution, states, that Æshna
clavata must be arranged with L. grandis and forcipata ; but it is nearer allied to Cor-
dulegaster annulatu.s, Leach (Libellula Boltoni o f Donovan’s British Insects.)
• T h a t F abric ius should have e rred in llie loc a tion o f a .species wliicb be liad never seen, b u t knew only
th ro u g h a ru d e figure, is n o t s u rp riz in g ; b u t surely such a c ircum stanc e can be no pro o f o f tli’e improprie tv o f
a sy.slem founded, a s Donovan c learly sliews. on cha ra c te rs o f stability, J . O. W.