90 DR. W. C. MINTOSH ON THE HAIRS OF CARCINUS MJENAS. 
the lines of the shell to the central depression. Hairs of the same structure are found 
round the abdomen of the males, though they are frequently short and abraded. 
Around the basal segment of the external antennz are numerous branched hairs; and 
at the triangular surface, and two flat ridges at f, many serrated ones. 
Fig. 8. 
Hairs of the Eye-sockets.—These fringe the cavity entirely around, a short distance 
within its margin. They are of two kinds, simple and branched; and none are more 
subject to parasitic growths. A somewhat unusual specimen of the latter sometimes 
attracts attention by its beauty and the novelty of its position. It is a little Alga, which 
spreads its tiny filaments from the trunk of the hair, and whose knotted aspect and fresh 
green colour stand in contrast with the surrounding masses. These hairs overlap the 
compound eye when retracted within its socket, and give the whole, but more especially 
the delicate cornes, due protection. By the admirable series of turns and twists which 
are made by the eye-cone in its withdrawal, most of the cornez are covered; but yet 
there remains a little corner (no doubt of great service to the Crab on fitting occasions) 
unprotected, and for the safety of this the hairs at that portion are eminently adapted. 
Masses of the acicular (margaric?) crystals so commonly met with in this animal were 
often seen amongst the hairs of this part. A portion of one of the hairs, with a cluster 
of alge attached, is shown in Pl. XX. fig. 4. 
Hairs of the Limbs.—I shall describe seriatim those on the various parts of the chelze, 
and superadd any peculiarities worthy of mention in regard to the same parts of the 
other limbs. The coccopodite has some short feathered hairs at its anterior and ventral 
margin, between the projecting articulation with the scalloped margin of the shell and 
the condyle between it and the basipodite; and a well-marked row of long hairs, some 
with sharp serrated points, on the posterior surface facing the first smalllimb. Similar 
arrangements are met with in the other limbs, only those of the fifth are longer. The 
basipodite is supplied with a fringe of branched hairs at its anterior margin, and towards 
