Boone, Annelida, Cruises of "Alva" 103 



and as many inches wide. Sometimes they are rounded and shape- 

 less, lying flat on the sand ; in other cases they are as long as six 

 feet and more and from one to three inches in diameter. The eggs 

 are small, 13 millimeters in diameter, nearly spherical or slightly 

 ovoid, very opaque and are enclosed in a thick chorion, which seen 

 by oblique light appears to be perforated by minute radiating 

 pores. The yolk is a light cinnamon color. Segmentation is almost 

 equal and the embryo gradually elongates and when 18 to 24 hours 

 old acquires a belt of cilia, in front of which two eye-spots appear, 

 and a broad band of cilia also appears on the ventral surface. The 

 first pair of setae appear on the third day, and the mouth is by 

 that time distinct. The larvae hatch on the third day and swim 

 freely for a day or two. The notopodial setae are first formed, 

 appearing from above downwards ; the neuropodial setae appear 

 at the end of the third or beginning of the fourth day. The larvae 

 then secrete a gelatinous tube, sink to the bottom of the vessel and 

 creep about there. There they lived for more than three weeks 

 and by the end of that time possessed eleven to twelve setigerous 

 segments." 



History: This limnivorous Polychaete, one of the largest 

 species found along the Atlantic coast of the southeastern United 

 States and in the West Indies, has attracted the interest of numer- 

 ous scientists, the original description of the species presented by 

 Stimpson (1856) having been augmented by Christian Lutken's 

 (1864) description of West Indian specimens from St. Croix and 

 the shores of the Antilles, under the name of Arenicola antillensis, 

 which was additionally recorded by Ehlers (1887), from Captiva 

 Key, Florida, collected by the United States Coast Survey Steamer 

 "Blake." In 1865 Prof. H. E. Webster, of Union College, New 

 York, gave the first record of this species from Bermuda, where 

 it was collected by Dr. G. Browne Goode. In 1879 the same author 

 reported the species from a fragmentary specimen taken on the 

 coasts of New Jersey. 



The first record of Are^iicola cristata from Naples was given 

 by Dr. R. Horst (1889), who found there two adult specimens, 

 also two immature specimens, possibly of this species. 



Mr. J. E. Ives, writing in the Proceedings of the Philadelphia 

 Academy of Natural Sciences, 1890, reported a colony of Are^ii- 

 cola cristata from Anglesea, New Jersey, and also specimens from 

 the Manatee River, west coast of Florida. 



