552 DR, L. ORLEY. 



Hatschek^ in his work, which furnishes contributions to the 

 knowledge of the development and morphology of the 

 Annelids. 



Two years later Hatschek- recognised this worm, described 

 its development, and provided Vejdovsky with material for his 

 researches.^ 



Like Hatschek, I found Criodrilusin the neighbourhood of 

 Buda-Pesthj and described it in a communication to the Hun- 

 garian Academy of Science.* Recently it was found by Rosa^ 

 in Italy, where it lives in the basin of the Po ; somewhat 

 earlier, too, it was noted by Panceri.^ 



I have no doubt that it exists in other parts of Europe, and 

 that only its habit of concealing itself has placed it amongst 

 rare and hitherto little known Earthworms. The following 

 description ought to lead to the discovery and to the better 

 knowledge of it. 



Criodrilus lacuum. HoflFm. 



1845. 'Die bis jetzt bekannten Arten d. Faun. d. 

 Regenwiirmer.^ 



A mudworm 4 — 12 cm. in length, and about 5 — 10 mm. in 

 breadth, of a dark brown or greenish colour dorsally, with 

 lighter, sometimes reddish colouration ventrally, with rusty- 

 yellow areolae, and milk-white, horn-like spermatophores near 

 the male genital pore. 



The body is quadrangular (though this is less noticeable 



1 • Sitzungsber. der Kais. Akad. d. Wiss. in Wien,' Bd. 74, pp. 442—459. 



2 " Studieu z. Entwick. d. Anneliden," ' Art. Zool. Inst. Wien,' Bd. 1. 



3 {a) ' Monograph, d. Encliytrceiden,' Prag., 1879. {b) " Ueber der Entwick. 

 des Herzens bei Criodrilus," ' Sitzungsb. k. bohm. ges. der Wiss..' Prag., 

 1879. (c) ' System uud Morphologic der Oligochajteu,' Prag., 1884. 



* (a) Amagyar. ' Oligochset. Fauna,' Buda-Pesth, 1881. {h) ' Revisio et 

 distributio specierum terricolarum regiouis pahxarcticae,' Buda-Pesth, 1885. 



^ "Nota sui Lombrici del Veneto," ' Atti del R. Inst. Yen. di Sci. Ictt. ed. 

 arti,' t. iv, s. vi. 



« " Catalogo degli anellidi d'ltalia," ' Atti d. Soc. Ital. d. Sci. Nat.,' 1875, 

 xviii, p. 201. 



