DISCUSSION OF SPECIES AXD THEIR DISTRIBUTION. 195 



THYRSITOrS VIOLACEUS, Bean. (Figure 209.) 



Thyrsitops violaccus, Bean, Proc. U. S. Nat. Mus., 1887, pp. 513, ,'511. 



A Thyrsitops with the body stout, its greatest width beiug exactly one-half of the height 

 at the anal origin. The greatest height of the body is one-half of the length of the head, 

 and is coutaiuLMl S times in the total length without caudal. The length of the head is one- 

 fourth of the standard length; its greatest width is contained -IJ times in its length. The 

 width of the iuterorbital area is slightly greater than the length of the eye, which is con- 

 tained nearly 7i times in the length of the head and 3i times in the lengtli of the np[)er jaw. 

 The least height of the tail ei^uals the width of the iuterorbital area. The length of the 

 snout equals twice the length of longest dorsal spine, and one-half the distance from the 

 tip of the snout to tlie origin of the spinous dorsal. The maxilla extends to the vertical 

 through the front of the eye. The length of the upper jaw equals 3J times the width of 

 the iuterorbital space. The mandible reaches to the vertical through the hind margin of 

 the eye; its leugth, including the fleshy tip, is 5 times the width of the iuterorbital area. 

 The anterior nostril is smaller than the iiosterior; it is situated in advance of the eye one 

 diameter of the eye. The posterior nostril is a narrow slit placed midway between the ante- 

 rior and the eye. Strong teeth on the intermaxillary and mandible. Three large fangs 

 anteriorly in the roof of the mouth; pseudobianchiic well developed; no trace of gill-rakers. 

 The spinous dorsal begins at a distance fi'om the snout wliich equals twice the length of 

 the snout; it is highest in the middle. The ninth and thirteenth spines are slightly longer 

 than the third spine and more than twice as long as the twentieth, their length equaling 

 one-half that of tlio snout. The soft dorsal is highest anteriorly, its longest ray, the fifth, 

 being nearly twice the least height of the tail. The caudal is forked; its middle rays about 

 one-half as long as the external rays. The anal origin is under the third ray of the soft 

 dorsal, its distance from the vent 2^ times the length of the dagger-shaped spine. The vent 

 is directly under the end of the spinous dorsal. The anal rays are longest anteriorly, the 

 fifth ray being neai'ly as long as the corresponding ray of the soft dorsal. The dagger- 

 shaped spine in front of the anal equals one-half the least height of the tail. The ventral 

 is immediately under the third spine of dorsal ; its first and longest ray equals three-foiu'ths 

 of the iuterorbital width. The fifth ray is about two- thirds as long as the first. The pec- 

 toral begins under the second dorsal sjiine; its length equals 2h times the width of the 

 iuterorbital area. It extends to the vertical midway between the fifth and six dorsal spines. 



The lateral line is well developed ; it descends gradually from the upper angle of the gill 

 opening, reaching the median line of the body under the soft dorsal. The scales are u-regu- 

 lar in shape, thin, elongate, cycloid, and deciduous. 



Color, i)urplish. The spinous dorsal, pectorals, ventnils, and inside of mouth blackish. 



Eadial formula: D. xx, i, 19+2 tinlets; A. 17+3 finlets; Y. I, 5; P. 13. 



TABLE OK MEASUREMENTS. 



Millimetera. Millimeters. 



Length to base of caud.il (44 inches) 1,115 



Greatest hei}i;ht of body 138 



Height at veiitvals 126 



Height at anal origin .' 112 



Least height of tail 40 



Greatest width of body 56 



Length of head 280 



(ireatest width of head 62 



Width of interorbital area 40 



Length of snout 117 



Length of upper jaw 130 



Length of mandible, with tip 203 



Length of mandibular tip 23 



Length of eye 37 



Spinous dorsal, from tip of snout 233 



Length of twentieth dorsal spine 25 



Length of fifth dorsal ray 78 



Length of last dorsal ray 20 



Length of second dorsal tiulet 28 



Caudal, length of middle rays 58 



Caudal, length of external rays 116 



Pectoral, from tip of snout 255 



Length of pectoral 100 



Ventral, from tip of snout 285 



Length of tirst ventral ray 30 



Length of fifth ventral ray 22 



Vent, from dagger-shaped spine 32 



Length of dagger-shaped spine 20 



Anal, from vent 45 



Length of fifth anal ray. 



Length of third dorsal 8]>ine 55 I Length of last anal ray 20 



Length of ninth dorsal spine 58 Length of last anal llnlet 28 



Length of thirteenth dorsal spine 58 



The type (Cat. No., U. S. iS'. M., 392S7) was received by the National Museum fioiu Mr. 

 W. A. Wilcox, agent of the U. S. Fish (Commission at (rloucester, Mass., and was caught by 

 Capt. Thomas Thomijson, schooner M. A. Iktston, on Le Have Bank, in 125 fathoms. 



