316 Proceedings of the Royal Physical Society. 



" As soon as the relations of the tentacles and the structure 

 of the arms in the genus Leachia are carefully considered, it 

 is obvious that Loligopsis pavo, Lesueur, and Leachia hyper- 

 horea, Stp., which have hitherto been referred to it, must 

 form a separate group. For in addition to the fact that the 

 latter species has, and the former seems to have had, tentacles, 

 both have narrow elongated fins, which extend along a large 

 portion of the body, and are strikingly characterised by their 

 enormous eyes, which almost meet on the ventral surface, 

 and by a funnel, which is shorter and smaller than that of 

 Leachia. The gladius agrees very well with that of other 

 Cranchias, but may, on the whole, be described as expanded 

 at the inferior extremity." 



" The generic name Taonius is chosen more especially with 

 reference to the longest known species, whose beautiful 

 coloured spots suggested the specific name pavo ; how far 

 similar spots may have been present on the body of my 

 species hyperhoreus, I cannot say. ... In case a division 

 of the genus should become desirable, I regard the older 

 species Lol. pavo, Les., as the type." 



It appears from these passages that Steenstrup regarded 

 Loligo pavo, Lesueur, as the type of his genus, and he did 

 not consider it essential to make a long and detailed state- 

 ment of its characters, because, as we have just seen, 

 d'Orbigny had already done this when he made the same 

 species the basis of his definition of the genus Loligopsis ; in 

 other words, Steenstrup's Taonius is practically identical 

 with d'Orbigny's Loligopsis. It is of great importance that 

 this should be clearly understood, because in 1882 Professor 

 A. E. Verrill constituted ^ a new genus, Desmoteuthis, based 

 upon a specimen captured near the northern edge of the 

 Gulf Stream, which he erroneously regarded as identical with 

 Taonius hyperhoreus^ Steenstrup. Another species, D. tenera, 

 Verrill, which is possibly identical with T. hyperhoreus,^ has 

 since been added to the genus. 



The most striking character in the generic diagnosis is 

 " Anterior edge of the mantle united directly to the head, on 

 the dorsal side, by a commissure, so that there is no free 



1 Ceph. N.E. Amer., p. 216. 2 /^^-^^ p 4^2. 



