REPORT ON THE SIPHONOPHOR.E. 159 



aspect, distinguishing the genus Abyla at once from the other Abylidse. Its outline is 

 irregularly triangular, and its sagittal axis (vertical in fig. 11) one and a half times as 

 long as the frontal (horizontal) axis. The three more prominent wings are so turned in 

 the inferior part that the basal edge of the right ventro-lateral wing (nx) occupies the 

 ventral half of the sagittal axis, and is just opposed to the dorsal wing (nd). The left 

 dorso-lateral wing (h 1 ), on the other side, occupies the left half of the frontal axis. 

 The five strong denticulate teeth, which form the basal ends of the five lateral win<rs, are 

 so turned that the basal mouth of the second nectophore, beyond the ostium of the 

 nectosac, forms a broad transverse or frontal fissure (like the mouth of a Plagiostome), 

 and perpendicular to this is a larger ovate longitudinal fissure (in the dorsal half of the 

 sagittal axis). 



Nectosac (figs. 8-10, iv 2 ). — The subumbrella of the second nectophore is very long, 

 subcylindrical, about six times as long as broad. Its apex touches the base of the 

 apical condyle (nq) and receives the nectocalycine duet (en), which passes through the 

 latter. The four radial canals of the subumbrella are regularly disposed, and united by 

 a small velum at its basal opening (fig. 11, uo). This opening is strongly protected and 

 partly hidden by the five basal teeth proceeding from the five wings of the exumbrella, 

 and described above (fig. 11). 



Siphosome. — The common stem, when contracted, is completely hidden in the 

 hydrcecial canal described above. When the animal floats quietly on the surface of the 

 tranquil sea it offers the peculiar aspect figured in figs. 1 and 2, PL XXXV., which I 

 drew from a living, intact specimen, 11th February 1867, in the Canary Island Lanzerote. 

 The longitudinal axis of the body (marked by the straight line of the expanded stem, on 

 the dorsal median line of the hydrcecial canal) is so inclined that it cuts the horizontal 

 level of the sea at an angle of 20°. The level is touched by the most prominent dorsal 

 parts of the body, the frontal crest of the first nectophore, and the uppermost part of the 

 dorsal edge of the second. A bunch of fishing tentacles issues through the basal opening 

 of the hydrcecial canal. 



Cormidia. — The Eudoxise attached to the siphosome, forty to sixty or more, are 

 regularly arranged in the usual ordinate manner, and do not reach sexual maturity before 

 being detached from the common stem. After being detached, they swim freely about 

 as Eudoxise, which assume the characteristic form of Amphiroa carina described above 

 (Genus 16). They are distinguished from other Eudoxidse by the six-sided prismatic 

 bract, with its large vertically descending dorsal phyllocyst, and the two horizontal 

 lateral canals arising perpendicularly from its uppermost apex (compare p. 114 and 

 PL XXXVI. ). 



