wn i:<ui>i.\ 01 NORTH PACIFIC \\l> \Ki \. I \ I WATERS FIBHBB 1 ■"> 



The BubsmbulacraJ spines are slenderer than ia usual, bul are grooved a1 ■ 

 on the distal pari of the spine 3ee Merrill, 1914, pi 78, fig 2 Professor Verrill's 

 t > j><- of m is is an unusually slender-epined specimen; two of mine have some- 



what Btouter aubambulacrals. These, as well as the inferomargmals, are stoutest in 

 tli*- large specimen with the fewest abactina] spinelets, noted above 



or deeper. Station! 



5 pi. 4, figs. i. 5 i7. 



There are, altogether, 40 specimens from depths of 50 fathoms to 93 fathoms, 

 taken north of Dnimak and (Jnalaska, and from the vicinity of the l'ril>ilc«f Islands 

 They arc therefore from southern Bering Sea. 



The largest specimen (station 3335, with K l l"> mm., r 36 nun . R 4 r: pi. 4, 

 figs i. -V i- fortunately from the greatest depth. It is comparable with large fully 

 grown examples from Bhailow water in the same region, and there is surprisingly 

 little difference, if the comparison is made with the slenderer spined Bpecin 

 The abactina] spinelets are smaller and a little more numerous. They are about the 

 same as in the specimens from Petropavlovsk ami northern Bering - In form 

 they air tapering ami blunt or else tin' tip may be compressed The sup rinal 



and inferomarginal spines an- distinctly grooved, but the spines are often Blightly 

 tapered and of medium width. Occasionally the Buperomarginals are Blightly 

 Bpatulate. There i- a single series of intermarginal Bpines extending about a third 

 the length "f the ray. The Bubambulacral spines are rather Blender, tapered Blightly, 

 with a groove on the (iiitci- side. They arc slenderer ami relatively longer than in 

 the Petropavlovsk examples, but arc not different from specimens from Btation 3242, 

 ami other -hallow w titer localities There seems to be no constant difference bet •■■ 



this lar^e fully grown example from 93 fathom- and -hallow water specimi 



In medium-sized ami smalli-h specimens from deep water (as stati 

 si fathoms) the abactina! spinelets are bo short that they are often no longer than 

 the numerous pedicellariae, the abactina) surface appearing a- il 1 with a 



close rather uniform nap. In other specimens the pattern of the abaotinal skeleton 

 can he readily traced bj reason of the stouter spinelets. 



cimens from intermediate depths show all -on- of variation-, with the 

 exception of the very heavj Bpatulate ventral spines An example from Btation 

 3281, :;•; fathom-, ha- coarse, w< U-spaced abactina] -pine- v hich are notched, pitted, 



and grooved a- in -hallow -w ater examples. 



Specimens with the weakest, most flaccid abactina! skeleton are from Btation 



:;.' 12, only 4.5 fathom-. 



The Crossed pedicellariae arc surprisingly large. In a Specimen from Btation 



;_■_'.". K about LIS mm ' the abactina] crossed pedioellarie <>f the abaotinal Burfact 

 range from 0.27 to 0.31 mm.: of superomargina] spines, 0.27 to 0.36 mm.; <>f the 

 inferomarginal Bpines, 0.31 to 0.36 mm. (see pi 6, fig. 7); of the Bubambulacra] 

 Bpines i»'iii to 0.38 mm. The actina] Btraight pedicellariae range from about 0.1 

 ii 9 mm., the form being shown in Plate 7, Figures 10, l La. The crossed pedicellariae 



are ahoiit as ltirgc a- those of the heavily -pined forma OnonuHa and arc larger than 



those of comparable -hallow-water example- having typical Bpines For instat 

 the inferomarginal crossed pedicellariae of the deep-water specimen- arc usually 

 between 0.34 ami 0.38 mm (station while in a comparable example from 



