122 HULLETIN OF THE BUREAU OF FISHERIES. 



lapping each other closely and arranged in but 5 rows, ranging in length from 0.006 mm. to 0.021 mm. 

 The whole armature is in the form of a crescentic band on either side, the concave face directed 

 foi ward. 



The relatively enormous spermatotheca and its relation tn the prostate gland is a characteristir 

 separating li. putchra clearly from li. coccinea and li. perKpicillniu. 



Type no. 181292, U. S. National MuHenni. 



Subfamily V. DIAULULINai. 



Body neither hard nor soft; depressed or suliilt|iicssi'il; untanim usually minutely villous, often 

 silky; tentacles digitiform; branchial aperture roun.l.-.l, < niiiihitf, branchial leaves tripinnate; ante- 

 rior margin of foot bilabiate, upper lip notched. Laliial aniiatinv none. Rhachis of tongue naked. 

 Pleune umltidentate, usually hooked. Penin usually unanufd. 



Oenn3 5. DIAULULA Bergh. 



THauluta Bergh. Gattuncen nordischer Dorideii. Arch. f. Naturgesch, XXXV, 1879. p. 343. On the Nudibranchiate Gast. r 

 opod Mollusoa of the North Paciflo Ocean (Sci. Results of the Exphjr. of Alaska, I, Art. VI). Proc. Acad. X:ii 

 Sci. Philadelphia, 1880. pp. 40-^6. System der Nudibr. Gasterop., 1892, p. 10.% Die Opisthobranchien, Biilkiin 

 Mus. Comp. Zool. Harvard, XXV, 10, 1894, pp. 171-176. 



Body fairly soft and depressed; notseum silky, minutely villmis; tentacles cligitiform; l>ranchial 

 aperture rounded, crenulate, branchia; tripinnate; foot rounded in front, bilabiate, upjier lip notched 

 in median line. Labial armature, none. Rhachis of tongue naked. Pleurae multidentate, teeth 

 hooked. Penis unarmed, prostate large. 



5. Diaulula sandiegensis (Cooper). 



[I>1. xxni. Hk. .-.; pi. .win, figs. 22-24.] 



Doris {Actinoq/dusf) Sandieuensis Cooper, Proc. Cal. Acad. Nat. Sci., II, 1S(;2, p. 204; III, 1S63. p. .^.s. 



Diaulula sandiegensis Bergh, Nudibr. Moll. North Pac. Ocean, Proc. Acad. Nat. Sci. Phila.. ISSO, pp. 40-10.— MacFarland, 

 op. cit., p. 41. 



Body soft, elliptical, velvety, the ends equally rounded, somewhat depressed. Mantle extending 

 beyond the head and foot everywhere except at the tip of the tail when the animal is crawling. Edge 

 of mantle wide and thick, slightly crenulate, projecting 6-8 mm. beyond sides of body in alcoholic 

 material. Dorsum everywhere minutely villains ami velvety, pale yellowish in color with dark brown or 

 black rings of varying size, number and posit imi (].!. .win, Kg. 5). In general these rings are arranged 

 in two longitudinal .series on each side of the median line with 3-6 rings in each row, but this is sub- 

 ject to much variation. The number may be increased to 20-30 irregularly scattered ring-like blotches 

 or may be reduced to 2 or 3 very faint ones, and between these extremes all gradations may occur. 

 The largest rings noted measured 8 mm. in diameter, though the average size is nearer 4 mm. for the 

 large ones. Small patches of brown may also occur among the rings. The general color of the dor- 

 sum may vary from light yellow to deep brownish yellow or even chocolate. 



Head entirely concealed by mantle, the mouth a vertical slit, the tentacles about 3 mm. long, 

 finger-like. 



Foot elongate oval, the ends I'dunded, the anterior end deeply l)ilabiate, the upper liii thinner, 

 broader, and bearing a median notch. 



Rhinci].liiires rimical, dilated in the clavu,s, perfoliate, with about 20-30 leaves, deeply retractile 

 into a conspic iiMiis sbeath with crenulate margin. 



Branchia' li deeply retractile, tripinnate plumes inclosing the anal papilla in a nearly complete 

 circle. Margin of the branchial sheath prominent, crenulate. Anal papilla conspicuous, conical, 3 

 mm. high, 1.5 mm. in diameter, attached anteriorly to the basal branchial ridge. Renal opening at 

 right and in front of anal papilla, inconspicuous. 



Pharyngeal bulb not large, about 4 mm. long, 2-3 mm. high and 3.5 mm. broad, the radula sheath 

 very prominent on the lower hinder margin, projecting as a compressed, rounded, keel-like structure 

 for about 1.5 mm. No labial armature save a simple cuticula. 



Radula rather broad, about twice as long as wide in anterior jiortion, yellow. Teeth in 19-22 rows 

 with from 26-30 teeth in each half row. 



