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 A HISTORY OF SUFFOLK course of about 15 miles to Breydon Water. The western end of Lake Lothing has quite a marine appearance, its stones being coated with the usual Algae of the upper littoral zone. Our gatherings are from the soft black mud of the channel beyond low-water mark. The sea was once known, on the occasion of an unusually high tide, to break over the top of the bank into Oulton Broad.' Breydon Water itself they describe as a large tidal basin about 4 miles long by a mile broad, to the west of Great Yarmouth, receiving the waters of the rivers Bure, Yare, and Waveney, and having a large proportion of its surface left dry at low water. From the Deben or the Stour, or both, they give the following species : In the family Cyprididae, Cypris pratensis, Brady and Robertson, at that date a new species, C. compressa, Baird, C. laevis, O. F. Mailer, C. gihba, Ramdohr ; Cypridopsis obesa, Brady and Robertson, Candona Candida (O.F.M.), C. lactea^ Baird, C. albicans, Brady ; in the Cytheridae, Cythere castanea, G. O. Sars, C. porcellanea, Brady, C. lutea, O.F.M., C. viridis, O.F.M., C. villosa (Sars), C.fuscaia, Brady, Limnicythere inopinata (Baird), Cytheridea torosa (R. Jones), Xestoleberis aurantia (Baird), Loxoconcha impressa (Baird), L. elliptica, Brady, L. pusilla, Brady and Robertson, then new, Cytherura nigrescens (Baird), C. robertsoni, Brady, C. gihba (O.F.M.) ; in the Paradoxostomatidae, Paradoxostoma variabi/e (Baird), P. fischeri, Sars; in the family Darwinulidae, Polycheles stevemoni, Brady and Robertson, a new genus and new species. To this list must be added from Oulton Broad, Lake Lothing, or Breydon Water, and in most cases from all three, in the Cyprididae, Cypris ovum (Jurine), C. reptans (Baird), Cypridopsis aculeata (Liljeborg), C. newtoni, Brady and Robertson, a new species, Candona compressa, Koch, C. kingsleii, Brady and Robertson, a new species ; in the Cytheridae, Metacypris cordata, Brady and Robertson, genus and species both new, Cythere pellucida, Baird, C. cicatricosa, Sars, C. antiquata, Baird, Limnicythere monstrifica (Norman), Cytheridea torosa, zr. teres, Cytherura Jiavescens, Brady, C. striata, Sars ; Cytheridea subulata, Brady ; Sclerochilus contortus (Norman), with var. abbreviatus ; Para- doxostoma abbreviatum, Sars, P. ensiforme, Brady. Of the species taken in the rivers above mentioned only Cvthere villosa and Cytherura gibba were missing from the expanded waters. From other re- searches may be added Cypria ophthalmica (Jurine) and Cyclocypris serena (Koch), obtained at Lowestoft in 1907 and submitted to Dr. Brady for identification, also Cytheridea elongata, Brady, and Cytherura clathrata, Sars, recorded by Brady in 1868, as dredged off Yarmouth by Mr. D. O. Drewett. Moreover, Paradoxostoma normani, Brady, appears to have been taken by Dr. Brady in Breydon Water, though at first considered to be a variety abbreviatus of Sclerochilus contortus.^^ To deal with this long series of genera and species so as to make intelligible their numerous and important but often microscopic differences, would demand a treatise to itself. It must suffice to allot them to their proper places under the rapid advances of modern classification, and to com- ment on a few forms in which this county may claim exceptional interest. All the species belong to the division Podocopa, in which the little animals are without a heart, and which is dis- tinguished in general from the other division, the Myodocopa, by having no rostral sinus to the shell-valves. The four families among which these species are distributed cannot be at once known apart by any single character. But as a rule the Cytheridae have a hard shell with uneven surface, while the shell in the other three families is thin and smooth. In the Cyprididae the second antennae usually have a brush of long plumose natatory setae, not found in the other families, and only the last two pairs of appendages are leg-like, instead of the last three as in the others. The so-called poison-gland and its duct, formed by the setiform flagellum on the basal joint of the second antennae, structures found in the Cytheridae and Paradoxostomatidae, are wanting in the Dar- winulidae. The Cytheridae are mostly marine, and cannot swim. The Paradoxostomatidae are distinguished by their slender, stiliform mandibles, adapted for piercing instead of biting. Cypris pratensis, according to Sars, should be called Cyprinotus pratensis, the change of genus in part depending on the strange circumstance that species of Cypris are found to be in many places never, or hardly ever, anything but parthenogenetic, while species of Cyprois and Cyprinotus are more connubial.'^ Cypris compressa, Baird, is now identified with Cypria ophthalmica (Jurine).^' C. laevis (O.F.M.) and C. ovum (Jurine), must be transferred to the synonymy of Cyclocypris laevis. The s^ezcs Cypris Serena, K-och, which since its institution has borne half a dozen different names, is now to be called Cyclocypris serena. Referring to this species and C. laevis, Brady and Norman, after re-defining their genus Cyclocypris, say : ' Professor G. O. Sars was certainly quite right in removing the two preceding species into the genus Cyclocypris. Our figures, pt. I, pi. xi, figs. 15, 16, were not correct as regards the setae of the limbs drawn, of which we now give correct descriptions in the character of the genus.'" It should be observed that figs. 15-16 have reference to Cyclocypris globosa (Sars), a species to which I was inclined to refer my Lowestoft specimens. These minute ostracods are tumid in shape, brown in colour ; the second antennae of the female " Ann. Nat. Hist. (1868), Ser. 4, iii, 372. " Brady and Norman, Trans. Roy. Dublin Soc. (1896), Ser. 2, v,- 720. " Ibid. (1889), Ser. 2, iv, 69. »« Ibid. (1896), v. 718, 719. 160