OPISTHOBRANf'HIATE MOLLUSCA FROM MONTEREY BAY. 119 



Radula colorless,- twice as k.nts as wide, not deeply grooved. The teeth in 20 rows, with 86-42 

 t.-eth in each row. Rhachis narrow, naked. Pleursv with 36-42 strongly hooked teeth (pi. xviii, fig. 

 1:5, 14). The first 2()-l'."i ..i th.s.- \;uy but little in size, the hook slightly increasing in length, theshaft 

 obliquely curved towar.l thr inr.liari Hne of the radula and bearing a thin, wing-like expansion on its 

 inner side. The outermost iL'-li; ]pleura? decrease very rapidly in size, are fitted closely together, and 

 become reduced to thin concave plates. 



The anterior genital mass is quite large, occupying the side and floor of the cavity in front of the 

 liver. Its outer face is convex, the inner side presenting two faces oblique to each other and of about 

 equal size, the crest between them being occupied by the spermatoeyst. 



The hermaphroditic duct ( pi. xviii, fig. 16, hd. ) emerges from the anterior lobe of the visceral mass, 

 is very delicate and short, and dilates almost immediately into its ampulla (pi. xviii, fig. 16, ha.) upon 

 the posterior inner face of the genital mass. The ampulla is large, grayish, 1 mm. in diameter by 10 

 Mini, in length, describes a short loop backward and then courses forward along the outer surface of 

 the proximal loop of the prostate gland to the anterior face of the genital mass, where it narrows, 

 gives off the spermatic duct, and passes on as the oviduct (pi. xviu, fig. 16, up. d. ov.). 



The penis ( imeputium) is 2 mm. long by 8 mm. in diameter, the everted glans is bluntly conical, 

 sliort, and unarmed. The vas deferens ( pi. x viii, fig. 1 6, v. def. ) is very long, narrow, looped upon the 

 anterior face of the genital mass, 0.5 mm. in diameter by about 15 mm. long, auA ]r.,^-i'< into the thick, 

 jiinkish-yellow prostate gland (pi. xviii, fig. 16, ]tr.), which lies in a loop diiv, icI |M,~iiiiorly along 

 the lower, inner margin of the genital mass, its inner i>ortion pinker and more di-t inn ly lolmlated than 

 the outer turn of the loop. Length of prostate 14 mm., its greatest diameter 2.5 mm. xVt the lower 

 margin of the anterior face the gland contracts into thr short .spermatic duct, which branches off from 

 the distal end of the hermaphroditic ampulla. 



The small spermatoeyst is oval in shape, 1 mm. long, and lies upon the vaginal duct, its duct quite 

 short and . .]iening into the uterine duct ( pi. xviii, fig. 1 7, sp. r. ) . The spermatotheca is large, somewhat 

 oval in outline, 3 mm. in longest diameter, and lies upon the crest between the inner anterior and 

 posterior faces of the genital mass. Its two ducts join it close together (pi. xviit, fig. 17, up. tli.) the 

 vaginal duct passing straight outward laterally (pi. xviii, fig. 17, va(j. d. ) and dilating into the vagina, 

 its length being about 3 mm., its average diameter 0.4 mm. 



The large albumin gland makes up a large portion of the genital mass, occupying the outer and 

 lower part, the yellowish nidamental gland being inclosed by it and exposed on the inner and posterior 

 faces of the ma.=s. A long, flattened, narrow vestibular gland lies on the outer posterior face of the 

 genital mass and opens into the vestibulum close to the vagina. 



Habitat: In rocky tide-pools from Point Pinos to Monterey, rather rare. T'sually most easily 

 found during July and August, but has been taken during the winter months as well. 



Th species name is given in honor of Dr. Harold Heath, assistant professor of zoology in Stanford 

 University, who has done excellent work upon the mollusca and to whose willing cooperation the 

 author owes much assistance in collecting Pacific coast nudiliranchs. 



Type no. 1.H1282 U. S. National Miiseum. 



Genus 4. ROSTANGA Bergh. 



Rostariga Bergli, Gatt. nOrdischer Doriden, Aroh. f. Natiirgoscli.. XLV. 1, 1S79. p. 3.S3. Malacol. Unters. Sup. H. II, I8.S1, 

 p. 99. System der Nudibr. Gasterop., 1892. p. 105. 



Notseum covereil wdth minute hispid papilla", l)ranchi;e of simply pinnate leaves. Rhachis of radula 

 naked; inner pleural teeth strong, with large body and small hook; the remaining ones less strong, 

 erect, the body smaller, the hook elongated and more slender, the apices of the outer pleurse with 

 slender denticles. 



4. Bostanga pulchra ^NlacFarhuid. 

 [PI. X.XIV, tig, S, pi. XVIII, tigs. 18-21; pi. XXI, Hg. 109.] 

 RiMavga pidchra MacFarland, op. clt., p. 40. 



Body elliptical, slightly depressed, the sides nearly parallel, the ends of body equally rounded, the 

 mantle ample, covering the whole body except the tip of the tail when the animal is crawling, (ien- 

 eral ground color (pi. xxiv, fig. 8) bright red, varying at times from light yellowish red to deep scarlet, 



