214 AITTOLYTITS AURANTIACA. 



while the posterior are also nearly circular. The buccal segment bears two pairs of 

 tentacular cirri, the dorsal being the longer. The succeeding acha3tous segment bears 

 three long tentacles — -a median and two lateral. The long anterior cirri are often coiled 

 like conical screws. 



The body reaches only about half the length of the nurse-stock, and its colouration 

 differs. After the first two brown squares a considerable and wider portion of the 

 dorsum has a central dark brown streak interrupted by pale bands at the usual intervals, 

 and with the lateral region of the feet of a granular brown. Behind this the body 

 tapers towards the tail and has the ordinary markings. The tail has two short cirri. 



Each of the feet of the middle region of the body bears a long tuft of simple bristles, 

 and the divisions of the feet are split deeply towards the centre of the body, the inner 

 portion being coloured, so as to add to the breadth of the central belt of brown. 



Habits. — The species lives well in captivity, and, like many others, constructs a tough 

 and translucent tube or case on the side of the vessel at the water-line. Some lived for 

 nine months at Murthly, which is about fifty miles from the sea. 



2. Autolytus aurantiaca, Claparede, 1868. Plate LXXI, fig. 3 — foot; Plate LXXIX, 



figs. 22, 22 a — bristles. 



Specific Characters. — Head small, rounded in front with a long median and two lateral 

 tentacles. Eyes four, black ; anterior pair the wider apart, whilst those on each side are 

 close together. Body about f inch long, tapered towards both extremities, of an orange 

 colour somewhat clouded in the middle from the intestine and its contents. Foot forms a 

 short blunt process, devoid of a distinct ventral cirrus. Dor sally is the short tapered 

 cirrus, then the massive setigerous region with bristles resembling A. pictus, and bifid at 

 the tip of the short terminal piece. 



Synonyms. 



1868. Procersea aurantiaca, Claparede. Annel. Nap., p. 219, pi. xv, f. 1. 



1874. „ luxurians, Marenzeller. Sitz. Akad. Wiss. Wien, p. 50, Taf. vi, f. 1, and Taf. vii, f. 1. 



1875. Autolytus (Procersea) aurantiacus, Marion and Bobretzky. Ann. Sc. Nat., 6 e ser., t. ii, p. 44. 

 1879. „ „ ,, Langerhans. Zeitsch. f. w. Zool., xxxii, p. 578. 



1885. „ „ „ Cams. Fanna Medit., p. 236. 



Habitat. — In a tube under a stone in a rock-pool at Paible, North Uist. It may have 

 been an accidental visitor to the tube. 



Madeira, amongst littoral plants, as well as in 20 fathoms (Langerhans). Shores 

 of France (Marion and Bobretzky). Mediterranean (Claparede). Adriatic (Marenzeller). 



Head small, rounded in front, with a long median and two lateral pale tentacles. 

 Eyes four, black, and about equal in size, the two anterior being wide apart, while those 

 on each side are close together. 



Body about f inch long, and with 70 — 100 segments (Marenzeller), tapered towards 

 both extremities ; of an orange colour, somewhat clouded in the middle from the intestine 



