POLYCH^TA SEDENTARIA OF THE FIRTH OF FORTH. 659 



simple elongated funnels, with their apertures directed forwards ; they are not 

 provided with such a series of digitate processes as are seen in Lanice and 

 Arenicola. The gonads are of the usual type, masses of indifferent cells attached 

 to the exterior of the nephrostomata, on the mediad side. The reproductive 

 cells become detached at a very early stage, and pass through the rest of their 

 development in a detached condition in the coelom. It is certain that the 

 spermatozoa reach the exterior by passing through the nephridia. In a series 

 of sections of a ripe male, we saw the nephrostomata and various parts of the 

 nephridial tubes quite distended with spermatozoa. Between the two posterior 

 nephrostomata and the body- wall, pass membranes which are rudiments of 

 transverse septa. There is also a rudiment of a septum between somites 

 2 and 3 (i.e., 1st and 2nd branchiferous). The ventral epidermic glandular 

 tissue, so conspicuous and extensive in Terebellidae, is restricted in Pectinaria 

 to the first two somites. 



Fam. Amphaeetida 

 Ampharete gracilis, Malmgren. 

 Ampharete gracilis, Malmgren, Nordiska Hafs-Annulater, p. 365. 



Dredged near Inchkeith, 29th October 1886 ; depth about 9 fathoms. 



Specific Diagnosis. — Abdominal segments, 13. Palmula composed of 12 to 

 14 setae, very slender, attenuated at extremity. Branchiae filiform, attenuated 

 at end, long, unequal ; anterior longer than the posterior. Uncini 5-6 dentate. 

 Anal somite crenulated at apex, without cirri. 



Length of our specimen, 30 mm. 



Analysing the somites here, as usual, we have cephalic — prseoral lobe and 

 buccal somite. Branchial — 3, the 1st bearing palmulse = modified notopodial 

 fascicle, and 4 branchiae on each side, the other two bearing only notopodial 

 fascicles. Thoracic — 12, each bearing notopodial fascicle borne on tubercle, and 

 transverse uncinigerous torus, with 5-6 dentate uncini. Abdominal — 13 with 

 uncinigerous torus = neuropoclium only, 4- anal segment without cirri (vide PI. 

 XLII. figs. 21 to 21 c). 



Genus Melinna. 



M. Sars, in describing Sabellides cristata (Fauna Littoralis Norvegice, ii. 

 p. 19), says that it perhaps deserves to be placed in a separate genus, but 

 decides provisionally to retain it under Sabellides. Malmgren made the 

 separation suggested by Sars, and instituted the genus Melinna (Nordiska 

 Hafs-Annidater , p. 371), of which he gives the following diagnosis (in Latin) : 

 — Praastomium smooth, without elevated frontal part, with anterior margin 

 transverse. Buccal segment produced into a ventral lip equal in length to the 



VOL. XXXIII. PART III. 5 D 



