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THE VOYAGE OF H.M.S. CHALLENGER. 
Disc odor is, Bergh. 
Discodoris, Bergh, Jalirb. deutsch. d. malacozool. Gesellsch., Bd. iv. 1877, p. 61. 
„ Bergh, Malacolog. Untersuch. (in Semper, Reisen im Archip. d. Philipp. Th. II. 
Bd. ii.), Heft xii., 1877, pp. 518-539; Supplementheft i. 1880, pp. 47-50; 
ii. 1881, pp. 108-112. 
Corpus subdepressum, circumferentia rotundata vel ovali, ut plurimum molle, supra 
miuute granulatum. Apertura brancbialis leviter crenulata, stellata vel bilabiata. 
Margo anterior podarii bilabiatus, labium superius plus minusve fissum. 
Laminae labiales e baculis minutis formatse. Lingua rhachide nuda, pleuris multiden- 
tatis dentibus bamatis. — Prostata magna ; penis inermis. 
This generic form is characterised by the flattened shape of the body, oval or 
roundish in circumference, and mostly of rather soft consistence, the dorsal side finely 
granulated. The branchial aperture crenulate, stellate, or bilabiate. The tentacles finger- 
shaped. The anterior margin of the foot with two lips, the upper one cleft in the middle. 
The labial plates, nearly surrounding the mouth proper, are composed of minute rods. 
The rhachis of the radula without plates ; the pleurae with many hook-shaped teeth. 
Prostate large ; penis unarmed. 
The Discodorides differ considerably from the Platydorides and the Asteronoti, and 
on the other hand approach the Thordisce, which still present the villous dorsum, and 
lack the armature of the labial disk. 1 
Very little is known of the biological relations of this group. Alder and Hancock 
saw the spawn of Discodoris concinna. Elliot observed the animal shedding pieces of 
the brim of the mantle (in Discodoris fragilis). 
The genus is particularly represented in tropical and subtropical seas ; only a small 
number of species has hitherto been examined or described. 
1. Discodoris boholiensis, Bergh. 
Philippine Sea. 
2. Discodoris meta, Bergh. 
Philippine Sea. 
3. Discodoris cebuensis, Bergh. 
Philippine Sea. 
4. Discodoris notha, Bergh. 
Philippine Sea. 
5. Discodoris morphcea, Bergh. 
Philippine Sea. 
1 Cf. my Malacolog. Untersuch., loc. cit., Heft xii., 1877, pp. 540-542. 
