296 MESSRS. E. HERON-ALLEN AND ARTHUR EARLAND ON 



specimen and the sketch. It has been reserved for us after the 

 lapse of 90 years to rediscover this organism in the Kerimba 

 sands, and though there can be no doubt about its rhizopodal 

 nature, its affinities and structure are so obscure that in the 

 absence of further specimens we are unable at the present time 

 to do more than record it under d'Orbigny's original name. It 

 will almost certainly require the establishment of a new genus. 



The leading zoological feature of the gatherings is perhaps the 

 great abundance and variety of the Miliolidse, of which we publish 

 notes upon 122 species, no less than 77 belonging to the genus 

 Miliolina, of which six are new to science. Interesting specimens 

 of Millett's species Miliolina durrandii have been found containing 

 ingested smaller Miliolids and other organisms, comparable with 

 the occurrence of a specimen of a rare variety Cassididina bradyi 

 var. elongata Sidebottom, which we found by accidentally crushing 

 a shell of Cymbcdopora bidloides d'Orbigny. The immense 

 abundance of the genus Peneroplis and the generosity of the 

 Council of the Society with regard to space have enabled us to 

 publish with all necessary text-figures a revision of the lituiform 

 species of this genus. The conclusion we have arrived at, after 

 considering every record from Linnasus's JVatctihos lituus and his 

 very confusing earlier authorities, is that the short stout spirilline 

 forms must be included under P. arietinus Batsch, the long narrow 

 forms must be P. cylindraceus Lamarck, and the specific name 

 lituus must lapse altogether, its place being taken by Chapman's 

 genus and species Monalysiduum polila* . 



In connection with the new genus Iridia, discussed at length 

 in Part I. of this Paper, a new point has arisen since the publi- 

 cation of that parti As regards the abnormal specimens ascribed 

 to the genus and figured in pi. xxxvi. (fig. 10), in which the 

 arenaceous investment is limited to an encircling wall, the two 

 faces of the shell being formed by transparent chitinous pellicles, 

 a. figure given in 1905 by Di\ Rhumbler of a new genus and 

 species named by him Vanhoeffenella gaussii f appears to be 

 identical with them. Rhum bier's specimens were from a depth of 

 400 metres in the Antarctic, and he states that the pellicle is so 

 transparent as to be visible only with special illumination. He 

 suggests that the object of the pellicles is to serve as windows by 

 which the animal may obtain some benefit from the last rays of 

 sunlight penetrating to this depth J. 



In the Kerimba specimens the pellicle is a stout chitinous 

 membrane distinctly visible with ordinary illumination, both dry 

 and in balsam, and in no way differing from the chitinous lining 

 which is present in all stages in Iridia. It does not appear from 

 Rhumbler's paper that he was acquainted with any other form 



* F. Chapman, 1899, Funafuti Fovaminifera, Journ. Linn. Soc, Zool. vol. xxviii. 

 p. 4, pi. i. fig. 5. 



f Verb. d. Deutscli. Zool. Ges. 1905, p. 105. 



X Qf. his description and text-figure 57 on page 216, in his "Foi-aminiferen der 

 Plankton-Expedition," pt. i. 1909. 



