54 MacFarland Preliminary Account of Dorididde. 



outer posterior angles, in front united into a veil with undulating margin ; 

 labial armature a ring of very short thickened rods; radula very narrow^ 

 the rhachis naked ; the first pleural tooth long, erect, hooked, the outer 

 one flattened, horizontal, denticulate. Glans penis armed. 



This new genus is dedicated to Mr. Timothy Hopkins, through whose 

 generous interest in Biology the foundation of the Hopkins Seaside Labora 

 tory was rendered possible. Its type is the following new species. 



20. Hopkinsia rosacea sp. nov. 



Type from Monterey Bay, Calif. No. 181,275, U. S. National Museum. 



General body outline elongate-elliptical, the ends abruptly rounded; 

 mantle firm, densely spiculate, much depressed, sloping gradually outward 

 to the thin margin of the foot, no mantle margin being present ; foot broad,, 

 abruptly rounded behind, in front with a broad triangular notch with 

 slightly thickened margin, the remaining margins thin and undulating ; 

 head broad, the oral tentacles very broad and united in front forming a 

 thin velar expansion with undulating margin, the rounded posterior angles 

 slightly auriculate ; dorsum thicky set everywhere with long gently taper 

 ing cylindrical soft papulae, the tips pointed or occasionally branched,, 

 many one-half to two-thirds the length of the whole animal ; rhinophores 

 perfoliate, cylindro-conical, without sheaths, perfoliate with about 20 leaves, 

 the clavus making up three-fourths of whole rhinophore ; branchiae 7 to 

 14, erect, simply pinnate, separate, arranged in a semi-circle or horseshoe- 

 form, the ends directed backward ; reproductive openings inconspicuous, 

 on right sideopposite rhinophores just below the outermost row of papillae. 



Color everywhere a beautiful deep rose pink. 



Length of large individual, 29 mm. ; width, 16 mm. ; height of body 

 alone, 5 mm. ; length of longest dorsal papillae, 18 mm. 



Pharyngeal crop strong, ellipsoidal, attached by a very short narrow 

 petiole; labial armature a ring of short thick rodlets in tesselated arrange 

 ment, width of armature, .4 mm; radula narrow, the teeth in 16 rows; 

 rhachis very narrow, naked ; pleural teeth single erect, long, flattened, the 

 base triangular, broad forming about one-third of whole length, the shaft 

 flattened blade-like, at the distal end a small blunt hook, total length, .63 

 mm.; the single uncinal tooth is much smaller, thin, depressed, triangular, 

 nearly horizontal, the posterior margin more or less pointed and irregularly 

 denticulate, length, .08 or .09 mm. ; greatest width, .076 mm. Prostate 

 gland very large, forming one-half of whole bulk of anterior genital 

 mass ; glans penis armed with minute hooks. 



Occurring under shelving rocks between tide-marks all along the coast 

 from Monterey to Point Lobos ; not rare. 



Stanford University, California. 



