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HOYLE: REPORTS ON THE CEPHALOPODA. 
I. INTEGUMENTARY ORGANS. 
A. The Mantle (Plate 10, Fig. 1) : — The hinder part of the inferior surface 
is covered by a patch of organs ( p), whilst in front of this they are placed in 
more or less regular linear series of which the following may be distinguished : 
1. A double row (m!) placed not very far from the median ventral line on 
either side and leaving a narrow free space between them. 
2. A single irregular series (m?) a little distance to the outer side of each 
of these. 
3. A fairly regular single series which commences on either side at the 
prominent angle of the mantle-margin and passes baekwards, converging 
towards the median line in its course (m3). 
All these six lines pass posteriorly into the patch of organs above mentioned. 
4. Still further to each side is a wavy series of small organs more irregular 
and more widely spaced, extending nearly to the posterior extremity of the 
body, whilst dorsally to these again and situated on each side of the mantle, is 
a row of about half a dozen. 
5. Along the margin of the mantle is a single series extending rather more 
than halfway round (m4). 
On the dorsal surfaee I detected only two or three minute organs, in à 
linear series parallel and near to the dorsal median line. 
B. The Siphon (s):— On the ventral face of the siphon are two groups, 
one on each side, leaving a clear space in the middle between them. Each 
group is roughly triangular in arrangement and consists of six to ten organs. 
C. The Head : — The inferior surface of the head presents a brilliant array 
of these little organs. Most conspicuous perhaps is a longitudinal series occu- 
Pying the median ventral line (41). Anteriorly this series bifurcates to pass 
up the fourth arm, and. posteriorly it also bifurcates just in front of the tip of 
the funnel and the two limbs pass backwards and outwards along the margin 
of the funnel-groove. Parallel with this median series are two others, one on 
eaeh side (A2), which start from the line of organs along the edge of the 
funnel-groove, and pass forwards to the outer edge of the fourth arm on each 
Side. Parallel with this line is a short row of three or four organs, between 
the funnel and the eye (A3), and in the same line with it in front of the eye 
is a group of four to eight (4). A semicircle of organs is found round the 
ventral margin of each eye aperture. 
D. The Arms: — Only the third and fourth pairs of arms are provided with 
these organs, On the fourth pair there is a single linear series on either mar- 
gin of the ventral face. The line on the inner margin is the continuation of 
the bifurcated median line on the lower surface of the head (A!) mentioned 
above. Tt extends about halfway,up the arm and then ceases. That in the 
Outer margin is a continuation of the series parallel with the median line (A?) ; 
after passing forward a short distance it becomes discontinuous and is resolved 
