Zoology.-] NATURAL HISTORY OF VICTORIA. [Annelida. 



with astonishing rapidity when disturbed. Neither Dr. Baird nor 

 other subsequent writers can be justified in uniting the genera 

 Megascolex and Perichceta, if Schmarda be correct in stating that 

 in his genus the setae go quite round the body, and in his P. 

 leucocycla from Ceylon he even says — " Die Kiickenborsten sind 

 etwas starker als die der Bauchseite." Schmarda is fully borne 

 out in this by Dr. Grube in his description and figure of Perichceta 

 Tahitensis, from Tahiti, in his essay on the " Anneliden " in the 

 " Beise der Osterreichischen Freggate Novara." Under any cir- 

 cumstances it is clear that our Australian species approaches more 

 nearly to Templeton's genus, and cannot belong to Perichceta, 

 which seems distinct from Megascolex by its smaller size, much 

 fewer body rings, and fewer and much larger setigerous papillae. 

 Still, as Templeton says, his Megascolex has 100 setigerous papillae 

 on each ring, while ours has only eight, disposed in four pairs as 

 in Lumbricus, I am constrained to use a special generic title Megas- 

 colides for the present form, and make it the type of a distinct 

 genus, which only differs as far as I know now from Lumbricus in 

 its great size, very much more numerous /ings, and the clitellae 

 formed of three separate short bands, not going round the body, but 

 being confined to the ventral side. 



The setae are extremely difficult to see and count, on most 

 specimens, from their extreme minuteness ; a slight brown speck 

 showing under a lens on the lighter flesh-color skin the places of 

 insertion of the setae and position of the rows in which, after great 

 trouble, I have satisfied myself the setae are alone developed, is a 

 great help in counting them. But, as I find on most of the rings 

 several other exactly similar brown specks, 15 to 18 on the mid- 

 ridge of each ring, those of one ring alternating irregularly with 

 those of the adjoining rings between the true setigerous ones, 

 forming the four pairs of longitudinal rows, but not really containing 

 setae, I have a strong impression that these may have been counted 

 as setae also by Templeton in his Megascolex, and it is not im- 

 possible that the longitudinal muscular plication (which also is absent 

 on the back) may have been confounded with the slight papillary 

 swellings from which the setae arise. Furthermore, Dr. Baird, 

 observing that all Schmarda's worms from the same locality as 



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