THYSANOTEUTHID^ — ONYCHOTEUTHID^. 31 



HiSTiOTEUTHis, d'Orbign}^ 1839. 



Etym. — Hisfion, a veil, and teuthis, a calaraary. 



Distr. — 3 sp. Mediterranean Sea ; off Nova Scotia. H. Bonel- 

 Hana, Fer. (xxvi, 33, 31). 



Bod}' short, cylindrical ; head long ; arms long, the three 

 superior pairs connected by a largely developed web, the ventral 

 pair free ; tentacles long, with six rows of dentated cups on their 

 clubs ; buccal membrane six-lobed. Pen short and broad. 



Family THYSANOTEUTHID^. 



Thysanoteuthis, Troschel, 185*7. 



Etym. — Thysanos., a fringe, and feuthis, a calamary. 



Distr. — 2 sp. Mediterranean Sea. T. rhombus., Trosch. (xxvi, 

 36, 3Y). 



Body with large triangular fins the whole length of each side ; 

 arms with lateral expansion of the skin, and two rows of pedun- 

 culated suckers, from which spring threads which are connate 

 with the surface of the lateral expansions. Shell file-shaped. 



Family ONYCHOTEUTHID^. 



The principal character of this family is the development of 

 hooks upon the arms, as a means of prehension ; they replace 

 the sucking disks to a greater or less extent, according to the 

 several genera. A few fossil forms occur. 



Gonatus, Gray, 1849. 



Diatr. — G, amoena, Moll, (xxvi, 38), is found on the coast of 

 Greenland. 



Body like Loligo ; aVms thick, with four rows of small suckers ; 

 tentacular clubs with many rows of small suckers, and a single 

 large basal cup armed with a hook ; siphon not connected to the 

 head, without valve. Gladius lancet-form. 



Onychoteuthis, Lichtenstein, 1818. 



Etym. — Onyx, a claw, and teuthis , a calamary. 



Syn. — Ancistroteuthis, Graj^, 1849. 



Distr. — 10 sp. Atlantic and Pacific O., arctic and tropical; 

 Mediterranean. 0. Krohni, Fer. et Orb. (xxvi, 39, 40). 



Arms with two rows of suckers, the rings of which are not 

 toothed ; tentacles thick, their clubs with two rows of strong 

 hooks, and at the base a rounded group of suckers, with which 

 they are supposed to unite the two tentacles, and use them in 

 conjunction as a, point cVapjJuij where great strength is required 

 in capturing their prey. Gladius lancet-form, with a conical 

 commencement. 



