DISCUSSION OF SPECIES AND THEIR DISTRIBUTION. 473 



sioii, is equal to tlie lengtU of tlie head; tlic preorbital extension about two-fiftlis of tlie 

 length of the snout. The preorbital processes are Hat, unarmed, and soniewliat divergent; 

 a ridge arises at tlio base of the preorbital proeess and extends to the angle of the pre^i)er- 

 euhini, where it terminates in a blunt spine; a hw ridge on the opereulnm, ending in a 

 rather incousiiicuous spine; anotlier above, and close to it, jiointing upward. Tlie length 

 of the opercular ridge of spines is nearly e<inal to the horizontal diameter of the eye. 



Jaws feeble and ajiparently toothless; barbels on the lower jaw so inconsi)icnous at 

 present as to be scarcely visible. 



The maxillary extends almost to fhf vertical through tlii' anterior iriargin of I lie eye; 

 the diameter of the eye is contained 4 times in the length of the head without its pro- 

 longations. 



The dorsal origin is over the tip of the opercular sjiiue; the origin of the anal ai>i)arently 

 behind that of the secimd dorsal; ventrals sliglitly in advance of the i)eclorals, and not so 

 far back, though their tips reach somewliat liey<ind the vent; jtectoials rather long; about 

 twenty-five rows of scales. 



The type, about '2 inches in length, is in the Museum of ('omjiarative Zo(ih)gy at 

 Cand)ridge, and has been studied in the iirejiaratiou of this description, but the example 

 being unique and very small, we have not ventured to examine it so closely as would have 

 been practicable with more material. It is, however, aiiparently a, well marked species, 

 resembling" in a. general way F. lonfiispittha. It was obtained by I'oey from the stomach 

 oi I'olyinivia nohilis, taken near Cuba, in dee]) water. 



1'1':RIST1''.1)1(i\ (;KAC1LI''., C >k ami lii-.AX, II. s. (Fi};iin':iS7). 



Body vei-y slender; its greatest height (bS millimeters) is nearly one-sixth of its length. 

 The length of the head to the tip of the prolongated rostral spine is 4S millimeters; without 

 the prolongations its length is .'5(i millimeters or twice the greatest height of the body. The 

 iuterorbital space is deejdy concave. The interorbital width (10 millinu'ters) equals one-half 

 the length of the snout including the rostral s])ine. The forehead descends gently towards 

 the snout and the snjiraoilutal crests are very litth; elevated. The lostral sjiine on ea<di 

 side is continued backward by a slight bony ridge ending in a blunt spine at the angle of 

 the preopereulum. The opercular spine is snmll, the length of the operculum with the 

 spine being about ecpial to the h^igth of the eye. The length of the snout witli i)reorbital 

 exten.sion (2!) millimeters) is a lit tie more than one-fourth of the standard length; the length 

 of the spine alone (13 millimeters) is nearly e(iual to the length of tin' mandible. The Jaws 

 are feeble and toothless. The length of theniaxilla (12 millimeters) is one fourth the length 

 of the head. The length of the mandible (l."* millimeters) is one-half the length of the 

 snout with the preorbital extension. The nuiudible has two groups of barbels, one on each 

 side of its lower edge. The length of the longest barbel (9 millimeters) equals that of the 

 eye. The barbels are subdivided into several fringes; the number of barbels on each side 

 of the mandible may be divided up into S or it clusters. The nuindible extends to the ver- 

 tical through the front of th(^ e\ e. Twenty six gill rakers on tlie first arch, the longest one- 

 half as h)iig as the eye. The longitudinal diameter of the eye (9 millimeters) is nearly 

 equal to the width of the interorbital space. (Ireatest width of the head over the preorbi- 

 tal ridge (15 millimeters) is one-half the length of the smmt including the in-eorbital exten- 

 sion. The spinous dorsal originates dire(;tly above the end of the (q)ercular Haj); the th-.st 

 spine is slightly the huigest, its length (lo millimeters) equals the length of the snout and 

 its projecting spine; it also eciuals the short diameter of the «'ye. The longest ray of the 

 second dorsal ( 1 1 niillimeters) is nearly (me fourth the length of the head. The least height 

 of the tail (.'! millimeters) is one third the length of tlie eye. The anal origin is under the 

 second ray of the soft dorsal; the tin extends as far back as the dorsal, tiie length of its 

 base (41 iiiillimeters) being 4 times the width of the interorbital area, the rays 

 aliout as long as those of the second dcnsal. The length of the middle caudal rays (12 

 millimeters) is four-thirds the length of the eye, the fin being emarginate. The ventral 

 base is under the pect(nal base, the tin reaching to the vent, its length (18 millimeters) twice 



