Gatty Marine Laboratory^ St. Andrens. 1G5 



smooth. At one point the tube had been broken and 

 repaired, but an angle on eacli side indicates the union. 

 The tube had also been fiactured in capture, and the annelid 

 had doubled itself into the largest fragment — the head and 

 tentacles being completely protected, but the tip of the tail 

 protrnded. 



This form has certain resemblances to the Heterocirrns 

 caput esocis of De St. Joseph, but the absence of eyes and 

 the structure of the anus and of the hooks indicate 

 divergences. 



Chat ozone A. 



A fragmentary form without snout or terminal region was 

 dredged on the 3rd September, in the ' Porcupine ' Expedition 

 of 1870, in the Bay of Tunis. In all probability it adhered 

 to the " tangles," which the naturalists then used, aftei- the 

 time-honoured practice of the coral-fishermen of the Medi- 

 terranean. The absence of the head and posterior region 

 renders diagnosis and description imperfect, but externally 

 it differs in certain respects from the northern Chatozone 

 setosa. Thus the body is more rounded, presents no dorsal 

 groove in the preparation, and the ventral groove is slightly" 

 marked, whereas both are usually distinct in C setosa. The 

 lateral bristles are much shorter, and though the specimen 

 is a small one, the basal deep brown hue and the great 

 breadth of the yellow tips, as at the tenth foot (for so all is 

 termed beyond the bend at the end of the shaft), are diagnostic 

 (PI. VI. fig. 4). The broad terminal blade ta])ers to a 

 long and fine point which is usually curved. Moreover, 

 whilst they are somewhat brittle, they do not exhibit that 

 proneness to split from the edge downward and backward as 

 commonly seen in C. setosa. Accompanying the foregoing are 

 a few narrow forms (PI. VI. fig. 4 a). Although proportion- 

 ally the crotchets should have been present in the portion 

 of the posterior region attached, only bristles exist. The 

 inserted basal region or shaft of the bristle is deep browUj 

 curved and dilated from the somewhat narrow end upward^ 

 and is striated. 



Two fragments of the anterior region of a Chostozone 

 which does not appear to differ from C. setosa, Malmgren, were 

 procured probably by the tangles in Bono Bay, on the coast 

 of Algiers, in the ' Porcupine^ Expedition of 1870. As no 

 crotchets are present, a certain amount of doubt remains, 

 especially as the bristles at the end of one fragment are 



