208 PROF. AV. B. BENHAM ON AQUATIC [Nov. 3, 



penial sac. There is no atrial sac, and the atrium itself is not 

 longer than the penis. In its general arrangement it resembles 

 the apparatus in Hesperodrilus albus of Beddard. 



The spermatheccB (one pair) extend through segments xiii. to xv. ; 

 the pore leads into a very slightly dilated muscular duct which 

 soon becomes narrow and is much arched dorsally; on passing 

 through the septum xiii./xiv. the duct, still narrow, becomes glan- 

 dular, and then opens into the ampulla, which occupies the hinder 

 part of segment xiv. and the whole of segment xv. 



Dime7isions. 20 mm. x \ mm. 75 segments. 



Localities. Lakes Manapouri and Wakatipu, Sovith Island of 

 New Zealand. 



Remarks. — This worm agrees closely with those South -American 

 worms for which the genus Hesperodrilus was founded by Mr. 

 Beddard* ; but Dr. Michaelsen t has shown good reason for merging 

 this genus with Phreodrilus owing to the discovery, in Kerguelen, 

 of a worm which in certain respects presents the characters of 

 both the genera. 



The discovery in New Zealand of two new species, this and the 

 following, belonging to the section of the genus hitherto found in 

 the Falkland Islands, South America, and Kerguelen, is a most 

 interesting additional fact in our knowledge of the geogi-aphical 

 distribution of the Southern Oligochseta. 



Phreodrilus mauianusJ, sp. n. 



This new species is founded on a single immature individual, 

 which, however, differs from any hitherto described. 



The ventral chsetse are, as usual, of two kinds, one of each in 

 each bundle, viz. — {a) a simple hook-shaped, single-pointed bristle, 

 and {h) a similar bi'istle with a very distinct tooth on its upper, 

 convex, surface. These chsetse measure 0"15 mra., and are thus 

 much longer than those of the species just described. 



The dorsal chsetse are capilliform, solitary, and commence in 

 segment iii. 



The oesophagus is narrow up to segment vi., where it dilates, 

 and is then constricted by the following septa. In the middle of 

 segment ix. the gut pi-esents a slight constriction, and the epithe- 

 lium suddenly changes in its character — the oesophagus passing 

 suddenly into the intestine. The dorsal vessel lies fi'ee of the 

 gut in segment x. and forwards ; a supra- intestinal vessel is 

 recognisable in segments vii. to xv. An enlarged commissural 

 vessel exists in segment x., and a contorted, swollen, heart-like 

 organ in the following segment (xi.), which appears to be connected 



* Beddard, Ann. Mag. Nat. Hist. (ser. 6) xiii. p. 206 ; & Evgeb. Hamb. Magalhaen. 

 Sammelreise, 1896 — " Naid. Tubificid. u. Tenicolen," p. 9. 



t Michaelsen, Oligoch. d. deutsch. Tiefsee Exped. 1902. 



X The speciiic name " mauianus," in which the syllable ati has the sound of ow in 

 cow, refers to the mythical Hercules of the Pacific, known to the Maoris as Maui. 

 The North Island of New Zealand owes its origin to Maui, who, while fishing from a 

 boat at sea, hauled up the land at the end of his fishing-line. Hence the original 

 Maori name for this island was " Te ika a Maui " — the fish of Maui. 



