The remaining families belong to the Cladohepatioa Ascoglossa, which among other
peculiarities haye a special form of radula, no jaws-, and no cnidosaos.
F amily X. HERMAJIDAS.
-dSolidiform animals which can be distinguished externally from the. Solids only
by (1) the absence of oral tentacles and the shape of the rhinophores, which are grooved
or auriform, (2) the position of the anal papilla, which is dorsal and in front of the
pericardium.
Genus 1. Hermæa L ovén.
See Bergh 10, pp. 4 49 ; 13, pp. 1—11 ; Trinchese 1, and Anatomia della Hermæa dendritica,
Bologna, 1877 ; Vayssière 2, pp. 128—132.
The rhinophores are auriform. The cerata are elongate and each row contains
several. There is no inglmies lucmlis. The teeth of the radula are usually quite smooth,
and when worn out lie in an irregular heap. The hepatic system is composed mainly of
two lateral canals; these send off diverticula which ramify within the cerata. The
complicated genitalia comprise two spermatothecas and several ramified glands, some J l
which extend into the cerata. The verge is armed with a spine.1
[The following genera, which are recorded only from the Mediterranean but probably
occur elsewhere, are allied to Hermæa, and, as far as is known, resemble it in all
points except those mentioned. They should perhaps_be regarded as sub-genera. (I)
Hermsdna: The teeth are serrulated on the lower margin. (2) Hermæopsis: The anal
papilla is lateral. (3) Plaàda : The hepatic diverticula within the cerata are simple and
not branched. j | | | |
1. H. bifida (Montagu).
(Pt. 5,Fam. 3, PI. 39.)
2. H. dendritica A. & H.
(Pt. 4, Fam. 3, PI 40.)
[Two less certain species have been described from neighbouring waters.
3. H. venosa L oven.
Ôfversigt af Kongl. Yetenskaps-Àkademiens Fôrhandlingar, 1844, no. 3, p. 50.
“ Gracilis, branchiis stylifonnibus, in series 7—8 digestis ternis v. qultemis, vase
gastrobr. (sic) crassiusculo, varicoso: vibraculis validis exacte auriformibns, apice
attenuate, obtuso; soleâ, antice rotundato-dilatatâ : quadrilinearis, albida, niveo punctata,
yasibus fuscis. Habitat inter algas, rarior.”
4. H. polychroma H esse.
Diag. de Nudibr. nouv. des côtes de Bretagne, Joum. de Conchyl., 3 Ser xiii 4
1873, p.346, ’ ’
“ Corpus prægracile, acuminatum, antice obtusnm, coeruleseens, lineâ rubescente supra
caudam omatum, collum luteum, lineis 2 violaeeis ad tentacula superna decurrentibus
notatum. Tentacula superna elongata, fusiformia, infra fissa, apice acuta, ccerulea.
1 As the anatomy of these small animals is extremely complicated and variable, it is not safe to
assume that the structure described by Bergh for particular species is really common to a whole group.
Velum latum, lateraliter expansum, arcuatum, coerulescens. Cirrhi branchiales, utrinque
in series 2 dispositiet 6—7 fasciculos-formantes, fusiformes, validi, complanati, sanguinei,
integri, apice luteo-aurantiaci, intus arborescentes. L. 20 mill. Hade de Brest.”]
Genus 2. Stiliger E hrenberg.
See Meyer and Mobius 1, pp. 13—14; Bergh 28, pp. 137—144; and 13, pp. 12—17.
This genus resembles Hermsea in all important points of structure, but differs from
it somewhat in appearance inasmuch as (1) the cerata are stout and swollen, much as in
Galvina; (2) the rhinophores are smooth, simple, and not split or grooved. The oral
tentacles are represented by two lumps.
Frcolania Trinchese is apparently only a sub-genus. It differs from Stiliger in having
the rhinophores slightly grooved.
1. St. bellulus (d’Orbigny).
= Calliopgea bellula (d’Orbigny).
= Embletonia mariaa Meyer & Mobiqs.
= Stiliger marias B ergh.
Genus 3. Alderia Allman.
Flattish animals with a general resemblance to Solids. • Head distinct and produced
into a lobe on either side, but tentacles and rhinophores are both absent. Foot expanded
and broader than the body, from which it is divided by a groove, so that the body, though
narrower, partly overhangs it. On this projecting part of the body are set the cerata,
two or three deep, somewhat inflated in shape, and containing ramified diverticula of the
liver. Anal papilla prominent, medio-dorsal, and nearly terminal. Radula short. Teeth
not denticulate; the disused teeth lie in an irregular heap. Verge armed with a spine.
1. A. modesta (Lov£n).
(Pt. 6, Fam. 3,. PI. 41; and Pt. 8, PI. VII, figs. 3—6.)
[This is the only certain species. A. harvardiensis Agassiz is described and figured
in Gould, 1, pp. 254—255, pi. xvi, figs. 226—228. I t is darker than A. modesta, has
fewer and smaller cerata and a more angular head. But the figure and description do
not altogether agree, and the form is probably a variety of our species. A. comosa Da
Costa (Ann. del Museo. Zoologico, Napoli, 1864, p. 32) is green with numerous long
cerata, and the anal papilla lies behind the pericardium.]
Family XI. ELYSIIDiE.
Shape flat, almost leaf-like. The anterior margin of the foot produced into short
processes. ■ On either side is a broad, flexible, wing-like expansion, which is separated
from the body by a distinct line. Behind the head lies the large pericardial prominence.
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