[235] CEPHALOPODS OF NORTHEASTERN COAST OF AMERICA. 445 



of a ridge, fitting into the siphonal cartilage; g, left gill ; h, rectum ; /<.', termina- 

 tion of the intestine or rectum ; i, ink-sac ; i', duct of ink-sac ; I, portion of liver,, 

 in position ; m', m', muscular columns connecting the head and siphon with dorsal 

 portion of the body ; H, systemic heart, or ventricle, crossed by the artery of the 

 ink-sac ; a o, bulbous base of anterior aorta ; o, ventral pallial artery, or median 

 branch of the posterior aorta, supplying the ventral parts of the mantle ; o', one of 

 the caudal arteries or lateral branches of the posterior aorta going to the caudal fin 

 and posterior parts of the mantle; a u, a u, branchial auricles; b v, afferent vessel 

 going to the gills ; b o, efferent branchial vessels, returning the blood to the ventri- 

 cle, their swollen basal portions acting as auricles ; v c, anterior vena-cava ; r, r, 

 ventral renal organs, two ventral sacculated branches of the vena-cava (on the left 

 side, the vein from the ink-sac and rectum is shown) ; r', r', two pyriform renal or- 

 gans, or sacculated and glandular portions of the posterior venae-cavse, directly con- 

 nected with r, r ; v, v c', lateral pallial veins, going to the dorsal sacculated divi- 

 sions of the vense-cavae ; v c", v c", two posterior venae-cavse, returniug from the 

 caudal fin and mantle ; S, the first stomach, or gizzard ; S', large, saccular coecal ap- 

 pendage of the stomach ; S", glandular, plicated stomach, in continuation with the 

 anterior portion of S' ; t, spermary or testicle; p r, prostate gland, with the vesi- 

 culse-seniinales and spermatophore-sac ; p, efferent sperm-duct or ' penis ' ; P, pos- 

 terior portion of the pen. 



Figure 2. — The same. Dorsal view of the reproductive organs, part of the renal or- 

 gans, heart, etc., dissected out. The lettering is as in figure 1, with the following 

 additions: vd,vd', vas-deferens, closely folded upon itself; v s, vesiculae-seininales; 

 s 8, spermatophore-sac ; p o, genital artery ; g o, spermatic artery and vein ; p t, part 

 of peritoneal membrane. 



Figure 3. — Loligo Peahi. Female in the breeding season. Oviduct, filled with ova, dis- 

 sected out. Ventral view, about $ natural size ; v o, commencement of convoluted,, 

 thin membranous portion of oviduct ; o d, entrance to glandular portion ; o d', gland- 

 ular portion of oviduct, surrounded by the large, laminated gland, %', the arterial 

 vessels of which have been injected; op, orifice of the oviduct. 



Figure 3a. — The same specimen, seen from the dorsal side. 

 Figures 2, 3 and 3a are from drawings by the author. 



Plate XXX. 



Figure 1. — Loligo Peahi. Embryo taken from the egg, ventral view, much enlarged; 

 a, a, a, ventral arms, tentacular arms, and third pair of sessile arms ; c, c, eyes on 

 stout peduncles or lobes from the sides of the head ; m, mantle-edge; h, branchial 

 auricles ; y, unabsorbed yolk-mass. 



Figure 2. — The same. An embryo, within the egg, somewbat more advanced than 

 figure 2, side view, less enlarged. The lettering is as in figure 2, with the follow- 

 ing additions: a', second pair of arms; a", third pair; a'", tentacular arms ; a"", 

 ventral arms; s, orifice of siphon ; o, otoliths; /, rudimentary caudal fins. Chro- 

 matophores are developed on the mantle. 



Figure 3. — The same. An embryo at the period of hatching. Ventral view, enlarged 

 about 15 diameters. The yolk-sac (y) is nearly absorbed ; a 3 , third pair of sessile 

 arms; ( a, tentacular arms ; va, ventral arms; b, beak; I, odontophore; r, teeth on 

 the radula ; s, siphon ; o t, otolith ; m, mantle ; /, caudal fin ; g, g', gills ; i, ink-sac ; 

 /, rectum; h', h', branchial auricles; w, u', rudiments of the stomach. 



Figure 4.— The same. Young, just hatched, seen as a transparent object, enlargedi 

 C diameters; from a specimen raised from the eggs at Newport, R. I., August 

 5th. Ventral view; a 3 , the third pair of arms; i a, tentacular arms; va, ven- 

 tral arms ; the suckers show out a, the tentacular arms ; b, the beak ; 7, odontophore ;: 

 e, the eye; /, caudal fin; g, gill; h, ventricle of the heart; h', h', branchial auri- 

 cles; i, ink-bag; m, mantle; o t, otoliths; s, siphon; s', base of siphon ; t, end of in- 

 testine; w, stomach; y, portion of yolk-sac, not yet absorbed. The chromatophores. 

 are omitted. 



