484 Prof. Mcintosh's Notes from the 



Staurocephalus minimus^ though he observes that the armature 

 of the proboscis in the latter at once distinguishes them. It 

 appears to me, however, that these resemblances are quite 

 superficial and probably have been suggested by the shape of 

 the head. The position of the short cephalic tentacles, the 

 structure of the proboscis, the form of the feet and the bristles, 

 the structure of the segments following the head, and other 

 particulars widely diverge, as indeed might be expected in a 

 form approaching the Hesionidss. 



3. On certain Processes formed hy Cerapus on Tubularia 

 indivisa. 



The members of the domicolous subdivision of the Amphi- 

 podous Crustacea are characterized by the very general habit 

 of forming tubes of various kinds, which constitute dwellings 

 as well as nests for the young, as in the common AinpMthoe 

 and in the Podoceri. Others, again, excavate tunnels in 

 tough clay or mud, like Corophium^ so abundant in the mussel- 

 beds of the Eden, or perforate wood like Chelura. The subject 

 of the present remarks^ apparently a species of Cerapus^ 

 closely allied to Ce^^apus difformis, Milne-Edwards, and very 

 prettily barred with red on the antennae, constructs groups of 

 flexible tubes (PL XITL fig. 9, a, a), which vary in diameter 

 according to the size of the occupant, on stems of Tubular^ia 

 indivisa^ very much as Stimpson describes in his Cerapus 

 ruhricornis on the shores of Grand Manan. Instead of being 

 formed, however, as Stimpson says, of " fine mud and some 

 animal cement," those of the British species have in addition 

 grains of sand, bristles and spines of annelids, hairs of sea- 

 mice, and many fine horny fibres, apparently derived from the 

 byssi of horse-mussels. 



On the same stems of Tubularia supporting the nests or 

 tubes are certain remarkable processes (PI, XIII. fig. 9, J, h) 

 which project from the coencecium like branches, and, indeed, 

 it was the unusual appearance and somewhat symmetrical 

 arrangement of these that first attracted notice. These fila- 

 mentous branches are of a dull greyish hue (that of the mud) , 

 and are very slightly tapered distally. The basal region, 

 however, is distinctly larger, especially where fixed to the 

 zoophyte. Their length varies from 3 to 4 inches, and all 

 seemed incomplete. They are smoothly rounded and resemble 

 the fine muddy tubes formed by certain annelids j but they 

 are quite solid and composed of the same constituents as the 

 tubes formerly mentioned, though, perhaps, the foreign bodies, 

 such as bristles and spines, are more conspicuous. These, 

 moreover, are neatly arranged with their long axis parallel to 



