Fam. 1, Plate 17. 



Genus 2. GONIODORIS,* Forbes. 



Corpus limaciforme, subangulatum, postice acuminatum, pallio parvo marginibus reflexis pasne' 

 obtectum. Caput ultra pallium prominens, in tentacula 2 labialia complanata extensum. Tentacula 

 dorsalia 2, laminata, non retractilia. Branchiae plumosse, non retractiles, postice in linea media dorsi 

 anum circumdantes. Apertura genitalis ad latus dextrum. 



This geniis has been very properly separated from Doris by Professor Edward Forbes, 

 who described it in the 'Annals of Natural History, 5 for March 1840.f It is distinguished 

 from Doris by the small cloak, the more angular body, and the tapering form of the posterior 

 extremity. To these characters we have added the exposure of the head beyond the cloak in 

 front, and the non-retractibility of the dorsal tentacles and branchial plumes. 



The additional characters we consider necessary for the more accurate definition of the 

 genus, though by thus restricting it, we exclude a beautiful group of the Dorididce, with a small 

 cloak, peculiar to warmer climates, and distinguished by the brilliancy of their colours, which 

 are generally disposed in stripes, spots, or marginal bands. In this group, which it was 

 the original intention of Professor Forbes to include in his genus, the cloak, though small 

 and narrow, is advanced before the head, and the dorsal tentacles are retractile within 

 cavities ; the body also has a more bi-lamellar form. The group in question appears to us to 

 constitute a well-marked genus, distinct from Goniodoris, from which we have consequently 

 excluded it. Goniodoris, as now restricted, contains a very limited number of species, 

 confined, so far as we at present know, to European seas. Herrmannsen erroneously states 

 that the type of this genus is the Doris gracilis of Rapp, a Mediterranean species, of deep blue 

 colour with white stripes, belonging to the southern group already mentioned. The true type 

 of Goniodoris we take to be the Doris nodosa of Montagu, of which the Goniodoris emarginata, 

 described by Professor Forbes in the paper where he characterises the genus, is a variety. 



This genus has the body of a sub -quadrilateral form, with elevated sides and tapering 

 posteriorly to a pointed tail. The cloak is small with a waved margin, generally reflected, 

 and is truncated or sinuated posteriorly immediately behind the vent. A median ridge, 

 sometimes not very distinctly marked, on the cloak, is continued conspicuously to the tail. 

 The head extends beyond the cloak in front, and is covered by a subvelar expansion, which 

 is produced into flattened oral tentacles at the sides. The mouth is inferior, without corneous 

 jaws, but with a spinous prehensile collar, and a denticulated tongue. The dorsal tentacles 

 are clavate and laminated, and are non-retractile. The branchiae are plumose, and surround 



* From ywvia, an angle, and Doris. f Vol. 5. 



