84 Bulletin, Vanderbilt Marine Museum, Vol. Ill 



Genus: SCYLLAEUS Linne, 

 Scyllarus americanus S. I. Smith. 



Plate 23, fig. A. 



Type: Founded on several specimens collected on Egmont Key, 

 west coast of Florida and deposited in 



Distribution: Known from ''Blake" station 142, Flannegan 

 Passage, and Egmont Key, Florida, Sands Key, Florida; Cuba, 45 

 fms., the Caribbean Sea and Brazil. 



Material examined: Two specimens taken in dragnet, off Knight's 

 Key, Florida, March 29, 1926; one specimen from Marquesas Keys, 

 Fla., 70 fms., collected by the ''Ara," William K. Vanderbilt, com- 

 manding. 



Technical description : Animal 67 mm. long, including antennae. 

 Carapace squarish, about 1 mm. longer than wide, with the 

 median dorsal line ridged and much elevated, broken into three 

 tooth-like processes, the median of which is the largest. The cervical 

 groove is well defined. There is also a pronounced ridge running 

 backward from the inner orbital angle, with two teeth above the eye 

 and interrupted by the transverse cervical groove. The median and 

 orbital ridges are covered with squamiform tubercles, which are also 

 present in a less pronounced degree in the wide, concave sulci which 

 lie on either side of the median ridge, between it and the orbital ridges, 

 the sulci being wider anteriorly. The lateral margin is covered with 

 squamosities and marked by four flat teeth anterior to the incision of 

 the cervical groove and one similar tooth posterior to it. There is a 

 transverse flat carina along the median three-fifths of the posterior 

 margin and a slight median emargination in the posterior margin. 

 The frontal margin of the carapace is truncate, shallowly emarginate 

 in the median region produced to a nodular lobe in advance of the 

 orbital ridge from which it is separated by a sinus. The orbital mar- 

 gin is closed, except for two incisions anteriorly, separated from each 

 other by a triangular node which lies anteriorly at the base of the 

 longitudinal ridge of the proximal article of the antennae. 



The antennulae lie between the large spatulate antennae and have 

 the peduncular article thickened, about two and one-third times as 

 long as wide; the upper surface is flat and truncated obliquely dis- 

 tally ; the second article is about one-fifth longer than the first article, 

 slender and cylindrical ; the third article is similar to the second but 



