FAMILY SEPIADA — LOLIGO. 3 
Louigo PUNCTATA. 
PLATE I. FIG. 1.—(STATE COLLECTION.) 
Description. Body cylindrical, tapering, about three inches in length, and with a slight 
ridge along the back, caused by the internal cartilaginous support. Body ends above in an 
acute point. The caudal appendage or fleshy fins terminal, broadly rhomboidal, and ending 
in an obtuse angle, nearly half the length of the body ; lateral edges rounded, perfectly smooth 
on both sides, attenuated atthe margins. Head moderately large, depressed; neck narrowed. 
Eyes large and prominent. Beneath the throat a prominent elongated muscular sac, opening 
externally by an irregular rounded orifice or vent. 
Arms ten, of which the two superior are shortest and smallest, and furnished with rounded 
cup-like suckers attached to the arms by a central ligament. These suckers extend to the 
tips, but become gradually smaller until they are scarcely visible unless aided by the lens. 
The same remark applies to the other arms, and it may be observed that the suckers are 
placed in no regular order. The second pair similar in shape, but more robust, and equal in 
length to the fifth or inferior pair. The third pair remarkably robust, and exceeding in length 
the preceding. Fourth pair longest of all, and equalling the length of the head and body; 
cylindrical, dilated towards the extremity, and ending in an acute tip: the suckers are 
arranged irregularly over the dilated part. 
Mouth central, sphincter-form, partly covered by an angular membrane with six short 
processes resembling the arms in miniature, and, like them, furnished with minute suckers. 
The internal cartilaginous support smooth, thin and translucent, resembling an ordinary quill ; 
its superior portion being comparable to the barrel, and its broad dilated extremity to the web. 
The upper portion triquetrous, hollowed out beneath, carinate above, and producing a corres- 
ponding elevation externally along the back : it ends in an acute tip above. This ridge along 
the back becomes gradually effaced towards the lower extremity. 
Color. The whole body, back of the head, fins and external parts of the arms covered with 
reddish rounded spots of various sizes; they are rather more sparse on the inferior surface 
of the sac. A row of these spots around the orbits, and behind the eyes they are so nume- 
rous as to give a darkened red appearance to that part. The external cuticle containing these 
spots is easily detached, leaving the denuded part of a pearly white. 
Length of head and body, 4°0 - 6:0. 
This beautiful Sqwzd is nearly allied to the L. pealii of Lesueur ; but this latter has its 
suckers arranged in two regular series, with the disks obliquely truncated. It has also a 
membrane along the lateral edges of the arms, and an acute termination of the caudal 
extremity. 
Dr. Gould, in his valuable report on the Invertebrata of Massachusetts, has furnished us 
with an exceedingly interesting account of the habits of these animals. Their colors vary 
every moment from vivid red to deep blue, violet, brown or orange. Their usual mode of 
swimming is by dilating their body and filling it with water ; the body is then suddenly con- 
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