Gaily Marine hahoralory^ Si. Andrews. 91 



flatteued and somewhat grooved ventrally, whilst iu series 

 from front to rear are tlie branchiae immediately behind the 

 long cirrus, a segment without bristles, and fifteen bristle- 

 tui'ts, with lamella for the hooks from the fourth bristle- 

 tuft backward — or twelve in all. 



The general hue of the dorsum is brownish pink, the 

 dorsal blood-vessel and the gills being deep red. The first 

 three body-segments have numerous brown specks (eyes ?) 

 on their posterior edges. The tentacles are dull })inkish in 

 mass. The caudal process is slightly yellowish. The intes- 

 tine shines through the translucent iridescent skin as pale 

 brownish, and a large blood-vessel is attached to it dorsally 

 below the more slender median dorsal trunk. This large 

 trunk appears to end in the deep opaque reddish mass below 

 the median fillet of the second bristled segment. The 

 median dorsal (superficial) trunk commences at the tail, 

 whereas the larger and deeper trunk on the gut appears 

 about the third hook-pad posteriorly, and the blood comes 

 from below. The former contracts from behind forward, 

 squeezing the vessel into a pale thread. The entire skin is 

 minutely reticulated with minute red^ blood-vessels. On 

 the ventral surface is a lateral trunk on each side, which 

 carries the blood backward, and which appears to form the 

 dorsal. The caudal process has pale papillcC along its sides. 

 The branchiae are usually two in number, though occasion- 

 ally the posterior on one side is absent. The anterior lies 

 immediately behind the long lateral cirrus and has the form 

 of a coiled process placed transversely, to which are attached 

 many membranous leaf-like jjlates, which gradually diminish 

 in size toward the tip, the whole somewhat resembling the 

 antenna of a lanicUicorn beetle or the scorpoid cyme of 

 Forget-me-not or JJorage. ^Vith the leaflets crowded so 

 thickly, the coiling of the axis and the diminution of the 

 lamellae at the tip present special advantage for aeration. 

 The second branchia arises from the dorsal edge of tlie 

 segmeni-ridge behind the former, and its structure is the 

 same. The crgans are firmly attached to the skin, and iu 

 softened examples are removed with it. In life the bright 

 red branchiae are most sensitive organs — now being gently 

 extended so as to expose each lamella separately to the 

 water, and again abiuptly contracted into a mass. 



Dorsally segmentation is less evident, but on the ventral 

 surface the median and lateral ridges give more definition 

 in this respect. A flat papilla, from whicli a ridge and 

 groove run to the mouth, lies within the long cirrus behind 

 the veil. Then a forward median fold behind the mouth i* 



