(laltij Murine Lahoratory^ Si. Andrews. 1 7 



and slopes with an unl)roken edge downward and forward to 

 the mid-ventral line, where a fissure separates the two sides, 

 each of w hich is |)rodu('ed into a prominent rounded edge 

 Mhich slightly overlaps its neighbour. The adjoining first 

 seute is indented in the middle line, thus giving a character 

 to the region. Whilst, therefore, the collar is largely 

 developed veutrally, a considerable part of the dorsum is 

 devoid of it. De St. Joseph found two pigment-spots (eyes) 

 over the cephalic ganglia. An otocyst occurs on each side 

 at the base of the branchiie. The branehite are of moderate 

 length (^V length of body), and their filaments are from 

 eiichteen to twenty-four in nundjer. Each filament has the 

 usual structure, and tapers distally, ending in a subulate 

 T>- hi tish terminal process, into which the chordoid axis, which 

 is remarkably attenuate towards the tip, does not go. The 

 subulate terminal filament, where no eye is present, has 

 a translucent thin margin, especially at the commence- 

 ment of its inner edge. It is at this region (viz. the 

 inner base) that the eye develops as a conspicuous dark 

 brownish-violet organ, a stripe of the flattened translucent 

 margin connecting its inner base with the line of the 

 pinnae ; whereas the distal part of the process is slender. 

 The pinnffi are of average length, and provided with a 

 chordoid unjointed axis. \\ hen injured, these organs are 

 readily reproduced from the filament, to which they give a 

 feathery appearance when the animal projects itself from its 

 tube. The branchire are gracefully spread like the flower 

 of a Convolvulus (Claparede). De St. Jose[)h describes the 

 exterior of the branchiae as white, or as brownish violet, or 

 alternately of these colours. Sometimes they are entirely 

 " couleur de rouillc ou gris de souris." In the examples from 

 Plymouth the colour was pale olive throughout, oidy the 

 exterior of the filament being marked by an interrupted 

 band of white, which broke up distally into is;)lated touches. 

 The remarkal)le delicacy of the pinna? is characteristic, each 

 ])ranchial process thus resembling a featiicr with its delicate 

 biirbs. When viewed from without, the branchial fan had a 

 slightly barred aspect from the arrangement of the white 

 touches. The pinnae are pale olive throughout. The eyes 

 vary much in size on the same specimen, and in one case 

 only a single large one was presimt, the rest being small in 

 varying degrees. All are double, with the terminal process 

 jjussing off between them. 



The anterior region consists of nine segments (six to nine, 

 De St. Joseph), eight of which bear pale golden bristle-tufts, 

 which slope in the preparations upward and backward, 

 .•ln;i. ct- Ma<j. X. llist. Scr. 8. Vol. xvii. 2 



