AUTOLYTUS EHBIEXSIS. 243 



and its rounded or ovoid distal region containing, as De St. Joseph points out, yellowish 

 corpuscles and rod-like bodies or bacilli (" batonnets," De St. Joseph). The setigerous 

 region forms a short cone with the lanceolate ventral cirrus soldered to it, the tip alone 

 being free. The bristles are translucent, with shafts slightly curved at the tip, the 

 bevelled region having an acute tip, and the terminal piece is comparatively short (Plate 

 LXXXVI, fig. 14) and has a simple hooked tip. The single rather strong spine 

 supporting the setigerous region has a mucro at the tip. In the posterior segments De 

 St. Joseph found a simple bristle with a curved point. 



Reproduction. — This was unknown to the earlier observers, but De St. Joseph found 

 that it showed the so-called alternation of generations. Thus in one form of sixty-five 

 segments, thirty-eight of the anterior are devoid of eggs, but the twenty-four following 

 have them, whilst the last three are free from them. The violet, green, brown, or dark 

 red female buds have the same dorsal tubercles as the nurse-stock, four eyes, of which 

 two are inferior, are devoid of proboscis, proventriculus, and stomach, but have a 

 rudiment of intestine. The feet possess bristles and a spine'like the adult, but in addition 

 the annelid has long swimming bristles. The male buds are pale rose- orange, with brown 

 testes from the third to the fourteenth. De St. Joseph further notes that the two 

 segments of the nurse-stock in front of the head of the bud are often full of ova or sperms. 



Eiirysyllis paradoxa was introduced to science (1864) by the indefatigable Claparede, 

 who, in spite of delicate health, did so much for the marine Annelids. He found it at 

 Port-Vendres, and described it under the name of Polymastia paradoxus, giving fairly 

 good figures of its general structure. He regarded the dorsal processes as homologous 

 with those of Ephesia, and he figured the compound bristles with simple tips. 



Simultaneously (1864) with Claparede, Ehlers gave an account of a new genus and 

 species — Eiirysyllis tubercidata — which he procured at Quarnero in the Adriatic. He 

 also alluded to the pinnate intestine, and described the compound bristles as having 

 simple tips, and the tips of the spines as furnished with a knob. So far as can be 

 observed this form would appear to be the same as Claparede's. 



Langerhans next (1879) met with it between tide-marks at Madeira, and he agrees 

 with the preceding authors in the structure of the tip of the terminal piece of the 

 compound bristles. To the spine he gave a clavate tip with a central process. 



Autolytus 1 ehbiensis, De St. Joseph, 1886. Plate LXXXVI, fig. 16— bristle; Plate 



LXXXVII, fig. 15— foot. 



Specific Characters. — Head rounded in front with four eyes having lenses 

 posteriorly and arranged in a trapezoid, the anterior pair being wider apart. Tentacles 

 normal, the median being much longer than the lateral, and the dorsal tentacular cirrus 

 fully as long. The dorsal tentacular cirrus is the longest appendage. Body of the 

 nurse-stock greyish, slightly flattened clorsally and ventrally, generally has a series (one 

 to seven) of buds, and much resembles Autolytus prolifer. Proboscis firm, sinuous and 

 narrow, with thirty minute teeth on its front edge, though a form with twenty is identical 



1 See p. 209. 



