204 AMERICAN JOURNAL 



EEMARKS ON NUDIBRANCHIATA INHABITING THE 



PACIFIC ISLANDS, WITH DESCRIPTIONS OF 



TWO NEW GENERA. 



BY W. HAEPER PEASE. 



Genus GONIOBRANCHUS, Pease. 



DescrijMon. — Corpus, depressum, oblongo-ovale, subgelati- 

 nosum, pes elongatum, postice ultra pallium extensum ; teu- 

 taculaB cervicales, retractilis, lamiuatis ; branchiis simplicis, 

 linearibus, elongato-lanceolatis, quadrangularis, transversa 

 laminatis, retractilis, interdum bifurcatis. 



Remarhs. — The chief peculiarity of this genus is the form 

 of its branchiae; they are simple, linear, of an elongate lance- 

 olate shape, and quadrangular, usually slightly compressed, so 

 that two sides are rather wider ; those sides are finely and 

 delicately laminated. The branchias are united at their base, 

 and on one species bifurcate. To this genus should be referred 

 Doris vibrata, Pse., 2^'>'0]nnquata, Pse., and 2>ic^<^, Pse., Proc. 

 Zool. Soc, 1860; also Doris 2nilchra, Pse., Proc. Zool. Soc, 

 1861. The branchiis of the first three were described as being 

 ciliated on their edges. On close examination of larger spe- 

 cies, the ciliiB prove to be the extension of the laminte beyond 

 the edges ; consequently those descriptions should be corrected 

 to read "laminated," instead of "ciliated." 



We add two new species as follows : — 



GONIOBRANCHUS ALBOMACULATUS, Pse. 



Descrii^tion. — Animal elongate oval, convexly depressed; 

 mantle rounded at either end, rather the widest at the middle, 

 upper surface covered with depressed tubercles of irregular 

 shape and size, and of a whitish color. Margins of the mantle 

 thin and slightly gashed, anteriorly slightly dilated when in 

 motion ; cervical tentacles, arising from short, swollen bases, 

 are large, elongate, cylindrical, tapering to acute tips, some- 

 what obliquely, delicately laminated ; labial tentacles cylindri- 

 cal, finger-shaped, rather long; branchias suberect, six or 

 seven in number, rather large, retractile into a tubular cavity, 

 laminae fine and close ; vent central, consisting of a short coni- 



