THK MYRIAIODA OF NOKTII AMKKICA. 1I>3 



a (lepressiuii occiip} in;; suUiis; luu^li. antnior pait riost'ly nhli(|iM'ly 

 s(iiat«; ln'iM'iit li. al»i>vi', t'sprciiilly on autnior pait, and alnn;; tin* «le- 

 pn'ssion, nunu'inus IhhscsIkk' likr ih*pr<'ssi«ins. lU'pnyinitorial pore 

 lar^e, plaiu'd on anterior part, a deep siilrns licliind. Anal sr^nient 

 slightly aii;;idatt'd. not passing \alv«'s: anal valv«*K scarcely niar^iiiu'd, 

 sparsely punctate: anal scale almost transverst'. liC^is extending- 

 slightly beyond sides ol" body. Segments, female, ."il-.'j.S; male, 51. 



Male: Less robust than female: coxa* of second pairofh';;slar^c, coxa' 

 of other le;is not produ«e«l: lemur with a sli;;htly swollen ovate knob: last 

 tarsal joint with an elongate sucker: sixth and seventh si'^im-nts swol- 

 len beneath: ventral plate of <'opulation fo(»t i'onvex, one-half as hi^li 

 as foot, a|)ex bilid; anterior copulafi()n foot short and heavy, outer 

 part i>lain, curling around inner, end slightly pointed, inner part heavy, 

 its inn<'r margin slightly c(Micave, a small win^ on its anterior surface; 

 l)Osterior <'opulati(»n loot somewhat hook like, its end rounded and 

 slij^htly bitid; on the inner side are three lobes; the first is lar;>e and 

 moderately flat, with its entire surfac<';;rajiulated; the second is spine- 

 like and arises just above the first: it is twisted, taperinj^, with its outer 

 s'lrfaee very rou;.;h; it en«ls near the beginning' of third, which is flat 

 an<l bent basalwards, its end concave. Len<;th. 40-.">0""" ; width. 4-5""". 



This si>ecies seems to bear little lesemblaiice to any other from Amer- 

 i<'a. It probably comes nearest to S. tlomini('((\ as shown by the form of 

 the ])osterior <opulati«)n foot, but the rest of the copulatory or^an is 

 entirely ditterent. 



In the collection is one .-specimen labelh'd "Surinam,'' and a very lar^e 

 number in another vial without any locality, but which I suppose are 

 from the same phu^c. 



5. Spirobolus caudatiis Newiiort. 



Spirobolits raudiitiis Newport. Ami. and Mag. Nat. Hist.. !'»)!•. isll ( Dcnurara) ', Jiihin 

 arhornin Sanssiiif, Linn. I'.iit.. 1^31. 1859 (>7. Tliomax). 



Segments, nuile, 51-53; female, 51-5(»; ocelli 40-55, in (J-8 series. 

 Male: Coxa' of none of the lejj^s noticeably produced or any other nmrk- 

 in^s of note ab(mt the le.ys. Ventral plate of co]mlation foot higher than 

 anterior i)art of first foot, but not so hi^h as posterior part; its end 

 rather suddenly pointed, slightly truncate. Anterior or inner part of 

 anterior copulation foot jxMntcd; end of i»osterior part rather blunt and 

 swollen. Posterior foot lon^- and slender, curved outwards and back 

 wards, the only part of coi)uh>tion foot i)roJe«'tinj;" out ofopeniu"; bitid. the 

 upper branch compressed, especially towards the end which is slightly 

 sinuate, its lower angle with a short, slender s])ine: lower branch lanceo- 

 late, not as long as upper, depressed, sides very thin and transi)arent, 

 edgesentire or very slightly sinuate. Ventral part of the anterior half of 

 seventh segment i^roduced into a blunt, triangular lobe. 



In the collection are a number of specimens which were obtained by 

 the U. S. Fish Commission at St. Thomas. 

 2097— Xo. 4U 13 



