138 PROCEEDINGS OF THE NATIONAL MUSEUM vol. i04 



Family Euryleptidae Lang, 1884 



Genus Prostheceraeus Schmarda, 1859 

 Prostheceraeus floridanus, new species 



Figure 87, a 



Material: One specimen sent alive by H. Humm of Florida 

 State UniA^ersity. 



Form: When crawling alive, extended, typical of the genus (fig. 

 87, a); narrow anteriorly with rounded margin and conspicuous, 

 slender, pointed tentacles; widening gradually posteriorly, then 

 narrowing slightly again to the rounded posterior end; when at rest, 

 broadly oval. Length, extended, 12 mm., but as the animal is 

 juvenile, presumably a much greater size is attained. 



Eyes: As usual in the genus, there is a pair of cerebral clusters 

 near the anterior end; eyes occur on the rounded margin between 

 the tentacle bases and numerously along the tentacles. 



Color: Very distinctive; most of the dorsal surface has a brown 

 network; laterally near the margin there is an irregular row of orange 

 dots interspersed among grayish black markings that extend nearly 

 to the margin; along the margin runs a fine orange line. This color 

 pattern contrasts with the white background. Tentacles black. An 

 attempt is made to represent the color pattern by stippling in figure 

 87,a. 



Digestive system: The tubular pharynx occurs in the usual 

 anterior location. The digestive system was plainly seen in the animal 

 when alive but is not evident in the mounted specimen. The main 

 intestiue extends back from the pharynx to a point about one-fifth 

 the body length from the posterior end and gives off numerous side 

 branches that anastomose into a small-meshed network extending 

 throughout the body. 



Reproductive system: There are no traces of any part of the 

 reproductive system, hence the specimen is juvenile. However, the 

 color pattern fm^nishes sufficient recognition. 



Differential diagnosis: This species is distinguished from other 

 species of the genus by the color pattern. 



Distribution: Taken Nov. 29, 1952, by dredging some distance 

 out in the Gidf of Mexico off the northwestern coast of Florida. 



Holotype: The specimen, mounted whole, is deposited in the 

 U. S. National Museum, No. 24632. The delicate animal was badly 

 distorted by fixation but the color pattern is well retained. 



