294 



BULLETIN OP THE BUREAU OF FISHERIES. 



Family LOLIGINID^ d'Orblgny, 1835 (em.) 

 Genus LOLIGO Schneider, 1784. 



Loligo Schneider, 17S4, p. 110. 



Lamarck, 1799, p. 10 (pars). 

 Verrill, iSSi, p. 307. 

 Hoyle, 1910. p. 410. 



Ten-armed cephalopods of moderate size, with an elongate, tapering, cylindrical body and large 



terminal triangular or sagittate fins. Mantle connectives of simple structure, the funnel cartilages 



elongate with a median groove. Funnel attached to the head by a pair of muscular bridles and 



equipped with an internal valve. Sessile arms angular; umbrella rudimentary or lacking, but the 



swimming membranes along the arms usually well developed. Only the distal portion 



of the left ventral arm hectocotylized. Suckers in two rows, alternating, bowl-shaped, 



furnished with a toothed homy ring surrounded by a raised margin. 



Distinguished from its nearest ally, the West Indian and Panamic Loltiguncula 

 (perhaps better to be regarded as a subgenus of Loligo), chiefly by the fact that the 

 female receives the spermatophores of the male upon a specially developed pad below 

 the mouth, whereas in the last-named group they are received upon a calloused patch 

 within the mantle near the left gill. 



Loligo is an important and abundant genus of cosmopolitan distribution, and in 

 number of species is exceeded by Sepia alone among the decapods. 



Type, Z.o/!90i;u/(7ar!.r Lamarck, i799,acommon European species. It is still more or 

 less of a mystery to me how any genus can logically take as its type a species not recog- 

 nized at the time it was founded and only subsequently established by another author. 



Loligo opalescens Berry, 191 1. 

 fig- 4-5-) 



(PI. XUII.fig. 5-8; pi. XUV, fig. 2-4; pi. XLV; pi. XLVI, 



? Lci/iVo Steamra Hemphill. 1892. p. 51, (nomen nudimi). 



? Hoyle. 1S97. p. 370 (8) (no description). 

 ^mm^slrephes iryoni Keep, 1904, p. 271, 351 (no description; not of Gabb). 

 Loligo pealti Jenkins & Carlson, 1903, p. 264 (physiolocy of nerves). 

 ? Loligo stearnsii Williamson, 1905. p. 1 29 (mere note). 



Kelsey, 1907. p. 42 (merely listed). 

 Ommastrephes iryoni Keep, 1910, p. 297 (no description). 

 Loligo opalescens Berry, 1911, p. 591. 



Body of moderate size; firm, cylindrical, narrow, elongate, slightly swollen near 

 the middle, thence tapering acutely to a rather sharp point behind. Fins large, about 

 half as long as the mantle; sagittate; very slightly lobed in front, barely continuous 

 behind, obtusely angled considerably in front of the middle; their margins thin, entire. 

 Mantle margin tnmcate, deeply emarginate between the prominent lateral angles on 

 eithersideof the funnel; produced above into a prominent, squarish, rostrum-like process, 

 rounded at the extremity, which is made up chiefly of a continuation of the dorsal 

 connective cartilage of the mantle around the tip of the gladius. Locking apparatus well developed, 

 comprising the just-mentioned cartilage in the nuchal region, besides a prominent elongate cartilaginous 

 groove and ridge on either side of the funnel; the latter simple, with a raised and reflexed margin (pi. 



XLIV, fig. 3,4)- 



Head small, narrower than the body, squarish, ornamented above posteriorly by three parallel 

 longitudinal folds of integument, the grooves between which correspond to the cartilaginous ribs of the 

 rostrum. Eyes large, not protruding. Siphon rather large, broad, and plump, with dorsal bridles and 

 a large terminal valve. 



Arms stout and rather short in the male, sometimes a little longer in the female;" unequal, the 

 dorsal arms considerably the shortest, but the proportions of the others somewhat variable, usually 



Fig. 4. — Loligo 

 opalescens, 

 inner aspect 

 of tentacle 

 club. [loi.l 



a Perhaps due to the different preservation of the material. 



