160 PEOF. OWEN ON NEW AND EAEE CEPHALOPODA. 



M. Velain was led, in his brief notice to the Academy of Sciences, to refer the huge 

 specimen to Steenstrup's genus ArchHeuthis. But in the later notice he specifies the 

 singularly truncate character of the arms, which do not narrow to a point as in all 

 other Cephalopods ; he refers also to a totally different hinder termination of the 

 " gladius." This, however, is not shown in the photograph of the entire animal ; nor is 

 the kind of difference specified. But, on the ground below cited i, the author proposes 

 to refer his subject to a distinct genus, "■Mouchezis" in honour of the commandant 

 (Mouchez) of the expedition. 



Of this specimen one of the tentacles, the beak, and pharynx were exhibited to the 

 Academy of Sciences ; and those parts are doubtless preserved in the Museum of Natural 

 History, Jardin des Plantes. 



If the stunted terminations of the ordinary cephalic arms of Mouchezis be accidental 

 to the individual specimen, the characters of the brachial acetabula, both as to structure 

 and arrangement, conform with those of the arm of the great Squid {Plectoteuthis 

 grandis) above described. Of the existence of folds of skin extending from the margins 

 of the acetabuliferous tract or the opposite parts of the arm of Mouchezis, no mention 

 is made. 



What is remarkable in the tentacular pair is their great length, almost equalling 

 that, relatively, in Loligopsis veranii'-. The prolonged attenuation of the pointed end 

 of the body approaches to that character in LoUgo suhulata, Lam.^; but it may be 

 remarked tlrat the corresponding end of the gladius in that species is not drawn out to 

 the same degree. 



Assuming a cephalic arm of Mouchezis to have been one fourth the length of the 

 extended tentacle, which is estimated at 16 feet, such arm would be less than half the 

 length of the great Ommastrcphic arm in the British Museum. 



The total length of Mouchezis, from the tip of the outstretched tentacle to the 

 pointed end of the body, is set down as nearly 23 feet, leaving 8 feet for the length 

 of the body. If, therefore, the tentacles of Plectoteuthis bore like proportions to those 

 of Mouchezis, the total length of that Cephalopod must have greatly surpassed the 

 Teuthid of the Isle of St. PauP. 



' " Sea dimensions, ses venteuses circulaires, garnies d"un cercle come finement dcnticule, leur disposition 

 BUT les bras, semblait motiver ce rapprochement, mais certains autres caractires Ten cloignent ; en particulier 

 la forme singulierement ecourtee dcs bras, qui paraissent tronques brusquement au lieu de terminer en une 

 pointe effilee, comme dans tons les Cepbalopodcs, ainsi quo la tenninaison inferieure, toute differente, de 

 I'osselet dorsal." — Op. cit. p. 83. 



" D'Orbigny, op. cit. Loligopsis, pi. 2. fig. 1. ^ Id. ib. Lolir/o, pi. 17. figs. 1 & 2. 



'' The above comparisons imply confidence in the accuracy of the dimension 7" 15 m. assigned to MoiKhezis. 

 It would be acceptable to Cephalopodists if figures of the natural size of the parts of the mouth preserved, 

 corresponding with those (Pis. XXX. & XXXII.) of Cook's Hooked Squid, were publiBhcd. Figures, nat. size, 

 of one of the cephalic arms and of the acetabular expansion of the tentacle of Mouchezis would bo equally 

 welcome. 



