AMBLYOSYLLIS LINEATA. 227 



Pionosyllis, so that the blade is bifid. The edge is probably minutely serrated, but 

 this could not be satisfactorily determined. 



The ventral cirrus arises from the posterior edge of the foot, is of a curved, 

 lanceolate form, and scarcely reaches the tip of the fleshy part of the setigerous region. 

 The occurrence of the ventral cirrus distinguishes this genus from both Autolysis and 

 Myrianida, and is another instance of the plastic nature of the appendages in the 

 Annelids. 



Reproduction. — The period of reproductive activity is, in all probability, in July. 

 A ripe male was found at Herm in August, and an advanced female, in the same month, 

 at Lochmaddy, North Uist. The changes in the form of the body and bases of the feet 

 at maturity are marked. In one the seventh segment was more dilated than the rest, but 

 this may have been accidental. The ova are of an orange or brownish hue. 



. De St. Joseph l describes the eggs as green or brown, while the sperms are white. 

 The natatory bristles commenced on the seventh segment. The eight segments filled with 

 the sexual elements are largely dilated, and their colouration is reduced to a simple brown 

 band. The eyes are largely increased in size, and cover almost the entire head. After 

 the development of the natatory bristles the animal swims with great activity. The 

 reproduction is direct, without alternation of generations. 



Malaquin 2 observed a young Amblyosyllis of eight bristled segments. Its proboscis 

 is long and coiled, but the larval pharynx is still visible anteriorly. The proventriculus 

 is present though small. The occipital wings and minute palpi are present. The stage 

 appears to agree with that of an Autolytus of twenty-two segments. 



Habits. — It is a most interesting and beautiful annelid in confinement. In repose the 

 cirri are gracefully coiled on the dorsum, but on touching the animal with a needle they 

 are stretched out, the opposite of what occurred in Mr. Hancock's specimen, though it 

 agrees in part with Mr. Dyster's experience as mentioned by Dr. Johnston. When moving 

 about a large trough (of a dissecting-lens) it occasionally coiled up the long cirri, and 

 swam through the water with a rapid wriggling motion like JEvame or Harmothoe. In 

 its native sites it cannot have much scope for locomotion, and this may explain its habit of 

 remaining quiescent for a long time in a glass vessel, its cirri being closely coiled. 



Specimens very readily fracture themselves in confinement, as, for instance, in a 

 bottle amongst other marine animals, or when put in spirit. Yet they may be kept alive 

 for a considerable time. Thus one obtained near the foot of the Lee hills at Lochmaddy 

 was carried in a small bottle (sij) therefrom to the summit of the mountain and across to 

 the shore on the southern side, where the sea-water was renewed. Moreover, ten or 

 twelve days thereafter it was transported to Murthly in Perthshire, where the coloured 

 figure was made and where it lived for six weeks. 



In a specimen from Herm the bases of the cirri were covered with minute whitish 

 parasites, probably the forms alluded to by De St. Joseph, 3 viz. Infusorians. He mentions 

 Trichodina Auerbachii, Cohn, Licrophora Auerbachii, Claparede, and an Acineta (Ophryo- 



1 Op. cit., p. 189 (1886). 



2 Op. cit., p. 423, pi. xiv, f. 30. 



3 < Ann. Sc. Nat./ 7 e ser., I, p. 190 (1886). 



