MacFarland Preliminary Account of Dorididee. 51 



1 or 2 compressed pointed tubercles ; behind the branchiae the 2 lateral 

 ridges unite in a low median crest to tip of tail ; branchiae 8, simply pin 

 nate, non-retractile, tallest in front, decreasing regularly in size from in 

 front backward; rhinophores stout, without sheaths, perfoliate; oral ten 

 tacles very short, lobiform ; foot linear, the anterior angles prominent; 

 general ground-color black, the dorsum and sides with numerous longitu 

 dinal rows of yellow spots, more or less confluent into continuous lines, the 

 intermediate spaces between the spots of each row greyish, also the basal 

 portion of frontal veil and the foot of same color ; mandibles light yellow, 

 very strong, each divided into a ventro-anterior cutting portion and a dorso- 

 lateral arched wing; radula arnber to dark brown in color, rather deeply 

 grooved ; teeth in 9 or 10 rows, the half rows not in a straight transverse 

 line; rhachis naked ; pleurae 2, unequal, the first smaller than the second, 

 alike in form, the shaft stout, flattened slightly, bearing a broad triangular 

 wing directed toward the median line ; the hook broad, large, bent toward 

 median line ; length of first tooth, 3 mm., the second .412 mm.; uncini 3, 

 prismatic, triangular in section decreasing in size from within outward ; 

 rarely a fourth rudimentary uncinus may be present. Glans penis closely 

 set with minute hooks arranged in rows. 



Length of animal, up to 23 mm.; width to 6 mm.; greatest height, 7mm. 



Found on red algae (Gigartimi) in rocky tide-pools all along the southern 

 coast of Monterey Bay; abundant. 



17. Acanthodoris hudsoni sp. nov. 



Type from Point Pinos, Calif. No. 181,289, U. S. National Museum. 



Body plump, highly arched, slightly higher and broader in front than 

 behind, oval ; dorsum soft villous, the papillae short, thickly set, bluntly 

 conical ; mantle margin broad, thick ; general ground-color clear translu 

 cent yellowish-white or pinkish, the papillae and branchiae tipped with 

 lemon-yellow, the mantle edged with the same color; head wide, the oral 

 tentacles broad triangular, a wide median anterior notch between them ; 

 foot broad, rounded abruptly in front, much less so behind ; rhinophores 

 long, tapering, clavus recurved ; perfoliate with about 24 leaves, the length 

 of stalk and clavus nearly the same, retractile into low sheath with pa 

 pillose margin ; branchiae 5, bipinnate, without sheath, widespread! ng; 

 pharyngeal crop large, hemispherical, very thick-walled ; labial armature 

 a pavement of minute hooks upon the lower and lateral walls of opening ; 

 lowermost portion free from hooks and bearing a broad slightly concave 

 cuticular plate, pointed behind, and forked anteriorly into 2 blade-like pro 

 cesses which project beyond the margin of the opening, its total length 

 being about .'J88 mm. 



Radula very narrow, deeply grooved; teeth in 27 rows; rhachis very 

 narrow, naked ; first pleural tooth very large, upright, compressed, its base 

 quadrangular in outline, the posterior border thin and wing-like, over 

 lapping the succeeding tooth ; anterior lower margin very strongly thickened, 

 rounded ; the upper anterior margin of the base prolonged upward into a 

 strong nearly straight hook, the upper inner margin of which bears a 



