80 E. a. Joshua : 



(luiifdineiisis, Purker (1). In NovenilxM-, 1910, I was fortunate 

 enough to obtain a number of specimens of the same animal near 

 Williamstown, and a careful exiimination convinced me that I was 

 dealing with a different species from the above-mentioned. The 

 accepted classification of the sub-family Oiirididinae, to which both 

 dunedinensix and the present species belong, is that of Ostergren 

 (2), who bases his arrangement on the presence or absence of cal- 

 careous deposits, and their disposition in the integument. Hubert 

 Lyman Clark (3) in his monograph on the Apodous Holothurians 

 gives a key to the genera and species comprised in the sub-family, and 

 adopting a suggestion of Semper's (4), he establishes the genus Tneni- 

 ogyrus to include those forms in which the wheel ossicles are collected in 

 papillae ; the genus Trochodnta, Ludwig, being characterised by the 

 wheels being scattered singly. The present species has the wheels 

 definitely aggregated, and could not therefore be placed in the genus 

 Trochodota, therefore further to consider its identity with T. duiie- 

 di/ien-^i-'i is perhaps superfluous ; it may, however, be pointed out that 

 a comparison of the description and figures of the wheels of dune- 

 dinen>ils with that given by myself of that of the present species, 

 shows marked variation. T. allani further differs in having but two 

 genital tubes, as opposed to several in T. diine.dinensis ; and in hav- 

 ing a contorted alimentary canal as opposed to the straight one of 

 Parker's species. Its differentiation from its congener Austral iana, 

 Stinipson (G), ;ind T. contorta, Ludwig, is fairly definite, and is ren- 

 dered easier in the case of the former from the fact of the species 

 having been revicAved by Clark (3). We have unfortunately no 

 description of the wheel of Australiaiut. but as regards the dis- 

 tribution of the sigmoid ossicles, Clark confirms Stimpson's origina) 

 observation, that they are in definite papillae ; in T. allani they are 

 invariably scattered. The genital tubes of T. Australiana are dis- 

 tinctly branched; in T. allani they are unbranched ; size, colour and 

 habitat are also different. 



F'rom T. ro/itnrfa, it differs in the structure of the wheel ossicle. I 

 am relying on Theel's (7) figure for this, as I could not get access 

 to Ludwig's original pii])er. T. ronfurfa has twelve tentacles. T. 

 allani ten ; 7'. ninforta has branched genital glands, T. allani un- 

 brunched. T. runtorta is viviparous (8), and though I have opened 

 many specimens of 7'. allani, \ have been unable to note this 

 peculiarity in it. 



Although I have pointed out above the error of Professor Vaney's 

 diagnosis, 1 think it but fair lo state that I think it was almost 

 certainly due to the f;u't that he was furnished with an incomplete 

 specimen; the slide Mibniittcd t-ontained in reality only about 2 cm. 

 of the anterior end of the animal. In this portion the aggregation of 

 the ossicles into papillae is not definite, and unless the wheels were 



