PROTULA TUBULARIA. 335 
west of Valentia, Ireland, on a sandy bottom (J. G. J.). A small variety occurs under 
stones between tide-marks at Herm, and was also dredged on shells off St. Peter Port, 
Guernsey (W. C. M.); Oban (J. G. J.); Connemara (A. G. Moore). Berehaven, Roy. Irish 
Acad. Exped., 1885 (small); Plymouth (Spence Bate and B. Rowe, Allen, Crawshay). 
West Coast of Ireland (Southern): the finest examples come from this region. 
Abroad it has been found at Cape Bojeader (Ehlers) ; shores of Cantabria (Rioja) ; 300 
fathoms off Norway (Sars); Mediterranean (Grube, Philippi, Panceri, Claparéde, Marion) ; 
Atlantic ; Adriatic (Marenzeller) ; shores of France (De Quatrefages, De St. Joseph, Fauvel). 
When the branchiz are removed, the anterior aspect of the cephalic plate presents in 
the middle the two somewhat triangular scars for the bases of the branchiew, each 
surrounded by a rim, whilst between and beneath them is the central mass connected with 
the mouth. Dorsally a fillet trends forward on each side to join the prominent curved 
and acutely pointed dorsal folds of the collar, which form a continuous frill on the lateral 
and ventral edges. The branchis are barred with pink and green (Montagu), those, 
however, from Plymouth being tinted only with red. 
Whilst a certain agreement exists between the cephalic region of Protula and the 
Sabellidee, the tenacity with which the branchie cling to the basal tissue is characteristic 
of the Serpulids. In Protula the branchiz form two comparatively short fans, the filaments 
in each of which range from thirty to sixty. They do not, as a rule, present a spiral arrange- 
ment in the preparations, though the tips are often coiled in various ways. Each filament 
springs from a basal web, which is elongated dorso-ventrally to accommodate the large 
series of these organs, and distally ends in a free subulate process (Plate CXXI, fig. 5) 
considerably longer, for instance, than in P. antestinum, and the short tip has a slight web 
b) 
on the inner side. The pinne are of moderate length and closely arranged in a double row 
along the mner border, the basal region of each being wider, and thereafter it gently 
tapers to the blunt tip. None of the camerated, chordoid tissue so characteristic of the 
Sabellid branchiz is present either in filament or pinna, though it is probable that cellular 
supporting tissue must be in both. The filaments are best developed toward the dorsal edge 
of the fans. Toward the tip of the filament the pinne diminish in length and end in short 
papillee at the base of the free distal processes, into which, as far as can be observed, only 
a blood-vessel enters. When thrown off, the vitality of the branchiz is considerable. 
A bilobed fillet lies between the bases of the branchiz dorsally, and at its ventral edge 
is a triangular process. Ventrally a wide gap leads to the mouth, which has a short fissure 
in the lower lip. In the small variety from Herm the subulate process at the tip of the 
branchial filament and the pinne are proportionally shorter, but the structure is the same. 
The dorsal lip, ciliated and often bordered with brown, is placed between the first dorsal 
branchie, and carries two palps. This is separated from the mouth by the ventral lip, which 
is colourless. 
The body (Plate CXVI, fig. 2) is somewhat broad anteriorly and tapers from the middle 
oradually to the tail, which has a terminal anus. It is somewhat flattened both dorsally 
and ventrally, a median groove occurring dorsally in the anterior region, and ventrally in 
the posterior region. The anterior region, moreover, has the broad membranous web con- 
tinuous anteriorly with the dorsal fold of the collar, and which passes laterally above the 
bristle-tufts, ending ventrally by joing that of the opposite side behind the last bristle- 
