22 CAMKOKNIA Af'AKKMY OK SCIKXCKS. 



The senera rt'latc'<l to Microscolex inav Ix- arnuigcfl as follows: 



I. Miilo pore in sniuito xviii. No|)bri<liii commences posterior to somite xiii. 



PosTouRii-rs nud PnoroDRiLrs, etc. 



II. Male pore in somite xvii. Nepliriilin eommeiioes in the (interior Homites ii to v. 



a. SpernidnctH open inilepmiilontl.v of the prostates. Riioi>or>Bli.DS. 



Kp.: minulim; novte-zetandiir. 

 I). Spermdiiets open in the prostate, close to the body-wall. 



1. The sotio of the inner conplcs (setio 1 nnd 2) in the vicinity of the clitcUnm are parnllel with 

 each other nnd do not converge toward any one of the genital pores. Nephridia commence 

 ill ii to iv. Mk'Iio.sc'Oi.ex. 



Sp.: moflenttis; titijerirnKiA. 



2. The setie of the inner conples (setio 1 nnd 2) in the vicinitj' of the clitellnm converge townrd 

 one or b'lth nf the giMiital pores. Nephridia commence in somite ii to v. Dklt.ama. 



Sp.: rfrr/atin: Troi/tri; Srtihftmi; Poultou!; iltihitt. 



DELTANIA. 



JJe/tunia Ei.'^on, Zoe, iv, 2-)0, October, 1803. 



Prostomiiini fiicroaclic.^ on somite i. ICii^lit .■^ctrc in four eonplos ventral and 

 lateral, hegimiino; in somite ii. The .setie of the inner couple- in the genital region 

 converging toward the male pore. Tiie seta? of the outer couple.s are further apart 

 than those of tlie inner couples. There are a huceal cavit}', pharynx, oesophagus and 

 sacculated intestine, but no gizzard, thyphlosole, or a^sojdiageal pouches. Clitel- 

 lnm, which is perfect, contain.^ three large somites and two outside smaller ones, 

 extending from xiii to xvii. No dorsal grooves. Testes in x and xi, free. Sperm-sacs 

 present, free. Spermatheca present or absent, vaii;ibl<' in position and shape. 

 Ovary one pair in xiii. Oviduct one pair in xiv. Two pair of ciliated rosettes in 

 X and xi. Spermducls open in xvii together with a large prostate which is placed 

 parallel to the segmental grooves. The spermducts join the muscular part of the 

 pro.state at the point where it enter.s the body-wall. The glandular part of the prostate 

 consists of two layers of cells. Penial sette open in the .same duct as the pro-state. 



The dorsal vessel with three pair of lateral hearts in x, xi and xii. No sub- 

 neural vessel. Only very few blood vessels on the nephritlia. 



Nephridia are of two slightly different kinds. Those in the first few anterior 

 somites, commencing in .eomite ii,opiMi in fioiit of nnd a little interior to the 4th seta, 

 wliilc tho.se po.steriiir to the former open in front of and a little lateral to the oil seta. 

 Tlic nephridia begin generally in ii, rarely in v. AH ne|du'idia furnished with a large 

 terminal bladder which in the posterior nephridia develop a ctecal prolongation. 



Small, transparent-glassy, more or less colorless worms with orange coloreil 

 elitellum, and living in moist, especially sandy soil. 



iSystemalic j)o$Uio)i. Under tlic genus Deltania I group all .species which 

 would otherwise be referred to Microscolex llosa, but which agree in having a ileltoid 

 arrangement of the ventral seta' surrounding the generative and especially the male 

 pores. With this character I believe a closer investigation of the species of Microscolex 

 will join others, principally in regard to the nephridia wiiicli have not l)een sulliciently 

 studied, probably on account of llic scarcity of specimens for research. 



Among species wbieli niiisl be icferred lo the genus besides those describetl 



