74 NATURAL HISTORY BULLETIN. 



Family, ASTRONYCID^, nov. 

 Astronycina, (pars) Ljung., Oph., Viv., 1867. 



Arms undivided, long, slender, coiled, not annulated nor 

 granulated. Disk with ten narrow radial ridges formed by 

 long narrow radial shields, covered with thin, smooth scales 

 or naked skin. Teeth stout, well formed, in a single row. 

 Tooth-papilla? one or two, conical, sometimes absent. Mouth- 

 papillre small, like conical granules, placed above the margins 

 of the jaw. Oral and adoral plates regularly formed. 



Upper and under arm-plates rudimentary or absent. Side- 

 arm-plates cover most of the lower side of the arm and pro- 

 ject laterally, bearing two, three, or more spines or tentacle- 

 scales, which may be either simple or hook-like. The gen- 

 ital slits are short, near together, in a depression near the 

 oral shields. 



Astronyx was the only described genus of this family, till 

 recently, when I was able to add to it a new genus, Astrodia, 

 (type A. tenmiisfina Ver.) from deep water off the U. S. 

 coast. 



This family includes only two genera, Astronyx M. & Tr., 

 and Astrodia. 



Astronyx lymani Verritt, sp. nov. 



Astronyx loveni Lym., Bull. Mus. Corap. Zool., vol. X, p. 282, pi. 

 VIII, figs. 136-138, young, ( non Mull. & Troschel). 



Plate VIII; Figures 4 — 4^. 

 Arms five, long, slender, coiled. Disk pentagonal with in- 

 curved margins, and ten high, long radial shields, which are 

 widely separated, curved outward in the middle and some- 

 what sinuous distally, the outer end a little clavate or 

 knobbed; the edge is serrulate with small scales. The radial 

 shields and disk are covered with a thin, smooth skin which 

 extends out on the arms above and below. Interbrachial 

 region below, in the dry specimen, concave or sunken, with 

 the two short but wide genital openings close together, near 

 the inner angle. 



