







RECENT BRITISH OSTRACODA. 



:57i> 



joint. It occupies a position similar to that of the Inarticulate seta which is uniformly 

 present in the freshwater Cypridse ; and I have noticed that in some of these (e. g. C/tpri- 

 dopsis vidua) the extremity of the seta forms a sac somewhat similar, lmt not so largel\ 

 developed. 



Genus 4. Notodromas, Lilljeborg. 



{Cyprois, Zenker; Newnhamia, King.) 



Carapace of very different shape in the male and female. Two eyes. Antrnnn' similar 

 | to those of Cypris\ the superior composed of seven, the inferior of six joints. Srku of 



the inferior antennae reaching beyond the apex of the terminal claws. Second pair 



- 



of jaws without a branchial appendage, pediform in the male. Abdominal 



and slender. Mucus-gland of the male large, beset with very numerous closely set 



whorls of stout rigid setae. Copulative organs of very complex structure. 



The genera Cyprois (Zenker) and Newnhamia (King) seem to be identical, or nearly 

 so, with Notodromas (Lilljeborg). The torose, tuberculated condition of the valv.-s of 

 Newnhamia cannot be considered as supplying a distinctive generic eharactor; while 

 the general contour of the carapace and the " boat-like plate " of the ventral surface an 

 remarkably in accordance with the English species N. monachus. A more important 

 difference (if borne out by further observation) is the presence in Newnhamia of a 

 branchial appendage to the second pair of jaw-feet. Mr. King states that this is present 

 in all the Australian Cypridse, though he does not specially mention it in his definition 

 of the genus or species of Newnhamia. But from the more 



left to infer the presence of this appendage. Mr. King describes Newnhamia as po 

 sessing also transparent ocular tubercles. 



o 



Notodromas monachus (Miiller). (Plate XXIII. figs. 1-9, and Plate XXXV1L fig. 3.) 



(1785), p. 60, tab. v. figs. 6-8; Baird, Natural History of 



Miiller, Entomostraca 



Monoc 

 Notodr 



? — j s , , 



British Entomostraca, p. 153, tab. xviii. fig. 6. 



figs 



figs. 1, 2, tab. XXV. fig. 16. 



o> 



De Oustaceis ox ord. tribus, p. 9.1, tab. viii. figs. 1-15, tab. xii. 



^.-Carapace obliquely subquadrangular, greatest height equal to two-. hir< s of t he 

 length, situated in the middle. Anterior margin broad, rounded at the angles and 

 expanded into a flattened lamina or flange. Ventral margin straight for about two- h , „1> 

 of its length, then bending upwards at an obtuse angle. Dorsa margin arched atooat 

 angular in the middle, whenee it slopes steeply to the antenor border, and wi h a bold 

 carve towards the posterior extremity, joining the ventral margin a an acu , v y 

 Seen f rom aW) the earapaee is ovate, pointed in front, and rounded ■*"**•£ * 

 Wth in the middle. The ventral smf'aee is bounded by two ~*^£** 

 areuate ridges (figs. 3, 6), one on eaeh valve, which together enelose a flattened lozeng. - 

 %>ed are! Wralle t the eontaet margin of eaeh valve »-»"*£ * 

 mueh less eonspieuous ridge, whieh, towards the trout, eurves "*£*•£*£ f ' 

 external ridge at an aeute angle, the union of the two formtng a shght elev ation (fig. 6«), 



