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Murr, F.E.S. ff [Read February 7th, 1912.] Puates XLIT-LX XVIII. ARRANGEMENT OF MEMOI I. INTRODUCTORY. II. ORISMOLOGY AND TECHNIQUE. III. MorrHoroey. A. ANATOMY. B. GENERAL. IV. FUNCTION. V. TAXONOMY AND PHYLOGENY. VI. ALPHABETICAL INDEX TO FAMILIES. VII. EXPLANATION OF PLATES. allie I. INTRODUCTORY. THE object of this memoir is to review the structure of the male genital tube throughout the Order Coleoptera. This is not equivalent to a review of the male copulatory organs. The modifications of the abdomen itself are extremely extensive and varied, but we have perforce omitted them, because the time at our disposal was scarcely adequate for the accomplishment of the work, - the results of which are here presented. Mr. F. Muir, having returned to England for a year’s vacation in order to recruit his health after a long period of arduous entomological work in the tropics, joined the senior author at Brockenhurst, and the two combined their efforts for the production of this memoir. A work of the kind is almost indispensable in the present state of Coleopterology, and the authors hope that it will be received as a much needed contribution to a great subject. A subject too as to which, notwith- standing its slight advancement, great misconception is prevalent. TRANS, ENT. SOC. LOND. 1912.—PART III. (DEC.) KK 478 Mr. D. Sharp and Mr. F. Muir on the Comparative The work has nearly all been carried out in the little laboratory attached to the residence of the senior author at Brockenhurst, and in a period of little more than twelve months. Each of the authors has devoted some independent work to it since Mr. Muir’s departure for Honolulu, and it is hoped that this fact will be accepted as some excuse for certain inconsistencies that may be discovered by a severe critic. The drawings that form so important a part of the work have all been made by the junior author, and consequently on him has fallen the difficult task of deciding as to the ventral and dorsal aspects of the structures. This is far from easy; it is, in fact, beset with sources of deception, as may be seen from the note (as to a discovery made by the junior author) placed in front of our descriptions of the family Scarabaeidae. A primary object of the authors being to make a review extending over all the Order, they could only hope, in the too short time at their disposal, to get together the necessary material by the aid of their friends. Appeals were therefore issued with this object, and met with the most obliging responses ; and we naturally desire to tender our warmest thanks to all those who have helped us in this and in other ways. We must mention first of all Mr. G. J. Arrow of the British Museum of Natural History; the only limit to whose kindness has been the reluctance we felt as to taking his attention from more important duties. Mr. Antwerp E. Pratt made over to us a considerable collection of Coleoptera from New Guinea, This enabled us to examine a number of specimens in the case of certain species, and has been most useful, though, for our purpose, it has been subject to the drawback of several of the forms being new or little-known species. Mr. J. C. Moulton of Sarawak, Mr. T. Bainbrigge Fletcher of Pusa, Mr. Arthur M. Lea of Tasmania, Mr. W. W. Froggatt of Sydney, sent us useful material. Herr Edmund Reitter of Paskau was so good as to select from his stores and send to us several forms we specially needed. In our own country Commander Walker and Mr. G. A. K. Marshall provided important material. Mr. Geo. Lewis has given us a few interesting forms. Mr. Ford of Bournemouth, and Mr. Janson of London gave themselves considerable trouble in the selection of speci- ‘Anatomy of the Male Genital Tube in Coleoptera. 479 mens for us. Mr. Hugh Scott of Cambridge University assisted us in every way that we asked. Mr. G. C. Champion and Mr. C. J. Gahan have been very good by helping us in the disagreeable task of naming our heterogeneous material. As regards the taxonomical and phylogenetic portions of the memoir it is desirable that we should say that they are drawn up to display the part that a knowledge of the fertilising structures should have in these two departments of Coleopterology. The senior author has for many years taken an interest in the taxonomy and phylogeny of Coleoptera, and it would therefore be absurd to pretend that, apart from consideration as to the sexual organs, he is in complete ignorance as to the bearings of other branches of anatomy, of physiology, of ethology aud of ontogeny on the two departments mentioned. But the junior author is comparatively a recent student of these departments; and the senior author, therefore, gave him a free hand in drawing up the tables, and has modified them but little. They represent, therefore, fairly well the results that may be obtained in taxonomy and phylogeny from a preliminary study of the male genital tube. We hope that we have made it clear, in other parts of the paper, that our work is only a very imperfect introduction to this comparatively narrow field of inquiry. But we believe the subject will prove to be of great importance when combined with the results derived through other lines of investigation. There is one point, however, in the memoir that has not been based on study of the aedeagus, viz. the families we have made use of. Though we shall have in the course of this memoir to propose several changes as to the families of Coleoptera, it must not be supposed that the families here dealt with have been decided on from the point of view of the structure of the genital tube. The forms studied were selected in the first instance simply by our desire to study these structures throughout the whole Order. We may, how- ever, say that though certain changes will have to be made, yet our impression is that most of the families at present in use in Coleopterology will have their validity substantiated by a continuance of this study. The second part of our morphological section deals with the nature of the male organs; and under the heading Phytophagoidea in the section phylogeny some more KK 2 480 Mr. D. Sharp and Mr. F. Muir on the Comparative speculative opinions on the same subject are given; but a brief elementary statement on this point will probably be found useful here. Two simple diagrams (figs. 239 and 239) have been made with the same object. They are really diagrammatic and do not represent any particular form. Let a glove be taken, a hole pierced in the tip of one of its fingers, a slender tube attached around this hole, this tube being placed inside the finger and prolonged into the hand-part of the glove: and we have before us a rough model of the genital tube. This structure lends itself to modification in the readiest manner. By traction on the slender tube the finger of the glove can be entirely drawn into the hand, with the result that the distal orifice becomes proximal. Let the glove finger be restored to its natural position and some hard patches be put on it, and the operation of invagina- tion be again repeated, and it will be noted how protean this simple arrangement can become. Further make some small folds on the finger, andisuppose these to grow out (after the fashion of the horns and processes on the heads of Lamellicorn beetles) and the reader will then have a general idea of the structures we are about to consider. The finger of the glove can be made by some folds to collapse in several layers, like a shut-up nautical telescope, and this telescopic arrangement can be carried to such an extent that Straus-Durckheim (M/elolontha vulgaris, pl. vi, f. 1) shows in a section of the telescopically collapsed tube no less than eleven superposed layers. We scarcely need to remark that the retraction and eversion of the genital tube are not brought about by force applied to the duct. We have had considerable difficulty in arranging our matter in a comprehensible sequence, and the different sections of the memoir are not conformable in this respect. We have endeavoured to diminish the inconvenience resulting from this by means of an alphabetical index of the names of families and groups placed immediately before the explanation of the figures. In the course of this memoir we have occasion to refer the reader to a passage of the historian Gibbon, relating to the Empress Theodora, the consort of the Emperor who rebuilt the great cathedral of Saint Sophia at Constantinople. We may fittingly close our introductory Anatomy of the Male Genital Tube in Coleoptera. 481 remarks by a quotation from the same chapter of this immortal author. He says, “A magnificent temple is a laudable monument of national taste and religion, and the enthusiast who entered the dome of St. Sophia might be tempted to suppose that it was the residence, or even the workmanship of the Deity. Yet how dull is the artifice, how insignificant is the labour, if it be compared with the formation of the vilest insect that crawls upon the surface of the temple !”—Gibbon, “ Decline and Fall of the Roman Empire,” chap. xl. II. ORISMOLOGY AND TECHNIQUE. The following is a list of some of the terms we have applied to parts of the male genital tube, and we add a few synonyms used by other writers. The letters in brackets are those made use of in the plates. This section is concluded by some critical remarks. AEDEAGUS. The median lobe and tegmen together. It is the Edeagophore of Blaisdell. AzyYGOS, or the azygotic portion of the male genital tube. It comprises all the unpaired portion of the tube from the body wall to the divergence of the seminal ducts, where the zygotic portion, or efferent ducts, ends (b-d and 5-1, fig. 239). BASAL-PIECE (bp). The basal part of the tegmen. It is the “basale” (Blaisdell); external lobes (Packard) ; basalplatte (Verhoeff); tambour (Straus-Durckheim). EJACULATORY DUCT (¢) or stenazygos is the slender portion of the genital tube from the seminal ducts to the internal sac or eurazygos. EuRAZzyGos (c-d and 5-1, fig. 239). The enlarged portion of the genital tube. FIRST CONNECTING MEMBRANE ((cml). The membrane connecting the median lobe to the tegmen. INTERNAL SAC (is). The enlarged portion of the azygos which is more or less evaginated during copulation. It is the sac interne (Jeannel); praeputialsack (Ver- hoeff), and forms part of the ejaculatory duct of most writers. LATERAL LOBES (/l). The distal portion of the tegmen. In the generalised trilobe type they form two free processes lateral of the median lobe and often en- 482 Mr. D. Sharp and Mr. F. Muir on the Comparative veloping it. They are the “deux branches de la pince” (Straus-Durckheim) ; mesostili in Procrustes, ipofallo in Lucanus and perifallo in Dytiscus (Berlese) ; apicale (Blaisdell), lateral lobes (Packard), Parameren (Verhoeff). MEDIAN FORAMEN (i). The aperture, or lumen, at the base of the median lobe through which the ejaculatory duct passes. MEDIAN LOBE (m/). The central portion of the aedeagus upon which the median orifice is situate. It is the penis of Straus-Durckheim, Verhoeff, Packard and many other writers, Korper (Lindemann), body (Hopkins), ipofallo in Procrustes etc., and penis in Oryctes (Berlese). MEDIAN ORIFICE (mo). The opening, or area, on the median lobe through which the internal sac is evaginated. It is the “Mundung ductus ejaculatorius” (Verhoeff), fornix edeagi (Blaisdell) and apical opening (Hopkins). MEDIAN STRUT (ms). A single strut, or a pair of struts, proceeding from the basal part of the median lobe. In some cases they are articulated to the median lobe, in other cases they actually form part of the median lobe without articulation or lne of demarca- tion. POINT OF ARTICULATION (pw). The point on the median lobe to which the lateral lobes are attached. In many cases the median lobe and tegmen are con- nected by intervening membrane and there is no point of articulation. SECOND CONNECTING MEMBRANE (cm2), The membrane connecting the tegmen to the termination of the abdomen. It is the prepuce of Straus-Durckheim (Melolontha vulgaris). SPICULE (sp fig. 224a). A sclerite attached by one end to the second connecting membrane. In many cases it is Y- or T-shaped. It is the Stengel (Lindemann), spiculum gastrale (Verhoeff), rod or fork (Hopkins), and is considered by some as being the last sternite. It is not infrequently similar in shape to another sclerite that pertains to another layer of the genital tube. Srenazyaos. Is the stenazygotic or slender portion of the azygos (b-c, fig. 239). TEGMEN (¢g). The term applied to the lateral lobes and Anatomy of the Male Genital Tube in Coleoptera. 483 basal-piece together. It is the ring (Hopkins), Gabel (Lindemann). VENTRAL PLATE (vp, fig. 19, etc.). A sclerite on the anterior ventral surface of the basal-piece in some Lamellicorns. In some cases the lateral lobes are consolidated to its anterior edge. The chitinisation of this part varies much. Zycos. Zygotic portion of the male genital tube; and is formed by the two seminal ducts (a—0, fig. 239) proceeding from the testes. METHOD EMPLOYED. In preparing this memoir it was necessary to make use of a great deal of dried material, some of it fifty and sixty years old, as our time was limited and we could not procure fresher specimens. In such cases we found the following methods acted very well and, if care was used, did not destroy the specimen. The dried specimens were placed in water and allowed to soak for a time according to the size and condition of the specimen, the water being heated if necessary ; when thoroughly relaxed the aedeagus was dissected out, either through the opening between the last dorsal and ventral plates, or the last segment was taken off, or the abdomen was taken off at the base, the aedeagus extracted through the basal foramen and, when necessary, the abdomen stuck on to the thorax again. The aedeagus was then placed in weak caustic potash for a time when the muscles would swell up and could then be dissected ; in cases where it was necessary to clear off all the muscles the caustic potash was used very strong. To get the internal sac evaginated was a more difficult. matter ; but with care it was possible to do this by the use of localised pressure, and with the aid of a very finely pointed syringe. By inserting the fine point into the median foramen and gently applying pressure the internal sac can be forced out in a manner, if not quite natural at least near enough to study its shape and structure. With fresh material it was a much easier matter, espe- cially with bulbous forms such as are found among the Staphylinidae; by placing the aedeagus in water and gently pressing upon the bulb the internal sac can be made to evaginate in a perfectly natural manner. To study»the position taken up by the internal sac 484 Mr. D. Sharp and Mr. F. Muir on the Comparative within the uterus during copulation it was necessary to take the beetles in copula, kill them in a strong killing- bottle and then dissect out the whole female organ with the internal sac of the male still in situ. We may here emphasise the great importance of extract- ing the structures without injury to the basal parts. It is necessary to give this caution because it too often happens that the dissections of these parts that exist in various collections have been made only with a view to examining the apical portions of the structures. Hence the basal parts are often found to have suffered serious injury. As there can be no doubt that the nature of the genitalia is destined to play a prominent part in the systematic study of Entomology, the terms to be used in it should be carefully considered. At present great confusion pre- vails. This is not a matter for surprise when the difficulties that exist are grasped. The male structures form parts and accessories of a genital conduit of which the female genitalia are the continuation and completion. Hence the male parts are really only comprehensible when studied in connection with the female parts; and this, moreover, when the two are functioning. The parts, in fact, have to be restored to the condition they are in during copula. The terms used in this memoir were of necessity selected soon after the commencement of our work, and we consider it advisable here to state how they appear to us at the conclusion of our undertaking. AEDEAGUS. This is a most convenient and useful term for the combination of sclerites in the two adjacent layers of the male tube. The term was, we believe, introduced by M. A. C. M. E. Foudras (Altisides, 1859, p. 32). It is probably derived from the Greek ta aidoia, signifying the genitals. The use of the Greek word may be seen in the notorious passage of Procopius quoted by Gibbon in footnote 24 of chap. xl of “The Decline and Fall.” We doubt whether a better term could be found for this middle complex of male sclerites, and we expect that a word will have to be invented for the corresponding (if not homo- logous) female sclerites. MEDIAN LOBE. This term is not free from serious objec- tions, but it is far superior to that of “penis,” which applied to Insecta is totally fallacious. The part in Anatomy of the Male Genital Tube in Coleoptera. 485 Insecta that most nearly approximates to the Verte- brate penis is the internal sac, the knowledge of which has been almost nothing until its recent in- auguration by Jeannel. The median Jobe appears to be sometimes a complex or amalgamation of more or less individualised sclerites. (Cf. Hydrophilus.) LATERAL LOBES. Though a very suitable term for the parts in the various trilobe forms, it is inappropriate in cases where the projections (if homologous at all) are medianly situate. Paramere is quite as good as lateral lobes. Cornua (meaning cornua tegminis) is also not free from objection, and accessory process is rather cumbersome. Tegminal lobes might do if the term tegmen be itself accepted. BASAL-PIECE. Perhaps this term may stand till more is known about the cases in which it is two pieces, and those in which it appears to be absent. INTERNAL Sac. Probably the term Vesica might be prefer- able. But this part of the conduit is so protean in form and development that it might be better to invent a term indicating a structure that is pre- dominantly membranous. TEGMEN. This term seems convenient and adequate for the layer of sclerites external to the median lobe. The elytra of grasshoppers are frequently called tegmina, but we do not think this objection to our use of the term a serious one. CONNECTING MEMBRANES. This term cannot be com- mended. It gives the idea that the sclerites are the important structures. But the tube may exist without sclerites and is it then a connecting membrane ? Other terms (such as Prepuce) that have been used for various parts are totally unsuitable. We consider that it is premature to endeavour to establish permanent terms for the parts of the complex genitalia of Insects till the various Orders have been more thoroughly examined and compared. 486 Mr. D. Sharp and Mr, F. Muir on the Comparative III. MORPHOLOGY. A. SPECIAL ANATOMY. Family CICINDELIDAE. Forms examined: Manticora tuberculata Deg., S. Africa. Omus californicus Esch., N. America. Cicindela tortuosa Dej., N. America. Therates lobiatus Fabr., New Guinea. Tricondyla aptera Ol., New Guinea. Figs. 29-31 of Pl. XLVI. Manticora tuberculata (Pl. XLVIT figs. 31, 31a, 310). Median lobe curved, tubular ; median orifice at distal end on ventral side, about one-fifth the length of lobe ; median foramen at basal end, as large as circumference of lobe ; dorsal edge forming a projection to which lateral lobes are articulated. Lateral lobes broad at base, with slender, free tips, Basal-piece shield-shape, connected to lateral lobes by a curved band broader in middle ; the lateral lobes are slightly asymmetrical and the distal end of each lobe lies on the left side of the median lobe. The internal sac is nearly as long as the median lobe ; at the point where the ejaculatory duct enters the sac there is a small chamber with chitinous walls (fig. 316) drawn out into a long, slender flagellum, with the external opening at its tip. Only the baso-dorsal part of the sac is evaginated, as a tongue, with the lateral edges turned down to form a groove, along which the flagellum passes (fig. 3la); the rest of the sac is crushed up like a concertina and the flagellum is pushed out, Omus californicus. Median lobe as in Cicindela but irregular in outline ; basal half of lateral lobes wider than in Cicindela, distal half tapering to a point. Basal-piece forming a thin V-piece on ventral side of median lobe. Internal sacwell developed, a thin, long, curved chitinous spine rising from the apex. Cicindela tortuosa (Pl. XLVII fig. 30). Median lobe curved, tubular, swollen along the distal two-thirds ; median orifice forming a slit along ventral side of the distal fourth of lobe ; median foramen at basal end. Lateral lobes slender, two- thirds as long as median lobe. Basal-piece V-shaped, connected to lateral lobes about one-third from their base. Internal sac large, Anatomy of the Male Genital Tube in Coleoptera. 487 and, when invaginated, coiled up, with a long, slender flagellum arising from apex with external opening of duct at tip (not shown in figure). Therates labiatus (Pl. XLVII fig. 29). Median lobe tubular, curved, thick, smaller and slightly flattened perpendicularly at base, median orifice at distal end, median foramen at basal end. Tegmen consisting of a pair of thin symmetrical lateral lobes, reaching to near tip of median lobe, and a wide V-shape basal-piece. Internal sac large with chitinous plates and two chitinous spines on sac, one curved and thin, the other short, thick and straight ; the duct enters at apex but not through spine (i, e. the spine is not of the nature of a flagellum). Tricondyla aptera. Median lobe curved, and tubular as in Manticora. The tegmen consisting of slender lateral arms and V-shaped basal-piece, as in C. tortwosa. Internal sac median size with large diverticula near apex and a large, strong bent spine on sac which is not traversed by the duct, the duct opening on apex of a small membranous tongue at the tip of the sac. Obs.—The Cicindelid aedeagus is similar to that of Cara- bidae in structure ; but is distinguished from all the Carabid types we are acquainted with by the presence of a basal- piece in the form of a sclerite on the ventral side of the median lobe. In this respect they resemble other Coleoptera more than the Carabidae do; but in the development of the internal sac with spines and a long flagellum they are more highly specialised. A great number of the Carabids are asymmetrical, whilst the Cicindelids are generally sym- metrical or nearly so. The diagnostic of the family is the same as that of the other families of the Caraboid series, except as regards the basal sclerite, which appears to be various in the series, Family CARABIDAE. Forms examined: Carabus violaceus L., Brockenhurst. Cychrus ventricosus (teste Leconte), California. Metrvus contractus Esch., California. Blethisa multipunctata L., England. Nebria brevicollis Fabr., Brockenhurst. Mor- molyce phyllodes Hag., loc.? Pheropsophus agnatus Chd., China. Clivina fossor L., Brockenhurst. Anthia sexgut- 488 Mr. D. Sharp and Mr. F. Muir on the Comparative tata Fabr., India. Tefius difficilis Sternberg, Nyasa- land, Pterostichus niger Sch., and oblongopwnctatus Fabr., Brockenhurst. Ophonus sabulicola Panz., Southsea. Laemosthenes complanatus Dej., Southsea. Bembidium biguttatum Fabr., Brockenhurst. Figs. 32-85 of Pls. XLVII and XLVIII relate to Carabidae. Carabus violaceus (Pl. XLVII figs. 32 and 32a). Median lobe long, tubular and well chitinised; median orifice extending about one-third along ventral side, the chitin of lobe thinning out into membrane of sac; median foramen running across basal end of lobe, the edge of which projects on dorsal side for attachment of lateral lobes. Lateral lobes thin, especially at distal end, nearly reaching to tip of median lobe. Internal sac well developed, covered with short dark spines on basal half; folds of membrane around opening of duct (od) complex (Fig. 32a). The figure shows a depression along the dorsal side which under fluid pressure becomes everted. Cychrus ventricosus, Somewhat like C. violaceus but median lobe more curved, especi- ally at base. Lateral lobes stouter and developed more perfectly, with tips slender and bearing a few hairs. Internal sac short (about one-third the length of median lobe) with long thread-like diverticula immediately ventral of opening of duct ; surface of sac studded with minute papillae. Nebria brevicollis (Pl. XLVII fig. 34). Median lobe curved cone-shape, the median orifice being situated at the small distal end, the median foramen at the large basal end. Lateral lobes attached to dorsal edge of median foramen, left lobe broad, flat, reaching to tip of median lobe, right lobe broad and flat, reaching about two-thirds along median lobe. Internal sac small and undifferentiated. Metrius contractus Median lobe short, deep, flattened ; the distal end produced into a curved blunt spine ; median orifice narrow, running along one- fourth of ventral side of lobe, near distal end; median foramen on basal end somewhat dorsal. Left lateral lobe narrow, spatulate at end, with fringe of long hairs along dorsal side, a little longer than median lobe; right lobe shorter, broader and produced to point, without hairs along edge. Internal sac large and complex. Anatomy of the Male Genital Tube in Coleoptera. 489 Blethisa multipunctata. The aedeagus of this species is remarkable by the small area of the median lobe that is chitinised, the larger part of the lobe being membranous. This species has also a very peculiar feature, inasmuch as a long strut extends forwards. This strut appears to be a process of the internal sac, and has nothing in common with the strut of Dytiscidae that at first sight appears to be similarly placed. It is unfortunately too late to add a drawing of this interesting structure to our plates. Mormolyce phyllodes (Pl. XLVI figs. 33 and 33a). Median lobe very short, stout, and funnel shaped ; median orifice large, across distal end, the edge of left side being drawn out into a narrow tongue; median foramen large, across base of lobe, with lateral lobes attached to edge on dorsal side. Left lateral lobe small and flattened, right lobe double the size of left. Internal sac when evaginated twice as long as median lobe, with blunt short diverticula near apex and the apical part granulated. It is possible that the sac as figured is not entirely evaginated near apex. In this paradoxical insect, the articulation between the lateral lobes and the median seems to be imperfect, but our preparation is from an immature example. Pheropsophus agnatus (Pl. XLVIII fig. 35). Median lobe short, pointed ; median orifice occupying median portion on ventral side of lobe ; median foramen basal. Lateral lobes small, irregular and sub-equal. Internal sac large, with blunt, short diverticula near base and on ventral side. Anthia sexqguttata. Median lobe forming an irregular tube, abruptly bent up dorsally near base ; median orifice a narrow slip along one-fourth of tube on ventral side near apex, continuing as a depression to near bend at base ; median foramen at basal end. Lateral lobes small, thick and irregular, right larger than left. Teffius difficilis. Very solid tubular median lobe, somewhat asymmetrical, with short thick lateral lobes attached to its dorsal basal point, the right lateral lobe larger than the left; median orifice at distal end, median foramen at basal end, slightly dorsal. Internal sac large, complex, covered with chitinous granulations. 490 Mr. D. Sharp and Mr. F. Muir on the Comparative The Carabid aedeagus consists of a more or less asymmetrical median lobe, with small but very varied lateral lobes attached to the dorsal side of the base of the median lobe, often very asymmetrical and often very much reduced. The basal piece absent, or rather not to be distinguished from the second connecting membrane. Internal sac often complex and well developed, contained in median lobe when invaginated (not passing through median foramen). When withdrawn into abdomen the aedeagus lies on its side. The absence of a basal sclerite separates this family from the Cicindelidae. Family PAUSSIDAE. The form examined appears to be the S. African Ortho- pterus smitht Macl. Our specimen has no locality label. Fig. 41 Pl. XLIX. Orthopterus smithi (Pl. XLIX fig. 41). | Median lobe a chitinous curved tube, thinner at distal end than at base ; median foramen as large as the lobe, with the lateral lobes attached to its dorsal edge ; median orifice formed by an asymmetrical slit at distal end, the right edge being produced into a small curved knob, the left into a curved flattened point. Right lateral lobe broad, and flattened, reaching to near apex of median lobe, left lateral lobe narrow and slightly shorter ; a small thin sclerite is attached to connecting membrane between the lateral lobes on ventral side (not shown in figure) and appears to be homologous to the basal-piece in Dytiscus. Internal sac fairly large and when evaginated funnel shape. This aedeagus is distinctly Caraboid and strongly reminds one of Nebria. If we may judge from a single dissection the family differs from Carabidae by the possession of a scleritic basal-piece. Family RHYSODIDAE. Form examined is a species from Queensland, not con- tained in the British Museum Collection. It is a large form somewhat resembling the European £&. swlcatus. Fic, 36 Pl. XLVII. Anatomy of the Male Genital Tube in Coleoptera. 491 Rhysodes sp.? (Fig. 36). Median lobe a strongly chitinised, curved tube, with median orifice on ventral side of apex and median foramen at basal end. Lateral lobes asymmetrical, the right large, flat and subtriangular, the left small and irregularly oval. Internal sac well developed, a large lobe arising from the apex armed with patches of hairs and chitin plates. This is a characteristic Caraboid type and must be placed near that family. Family PELOBIIDAE. Pelobius tardus Herbst, from Brockenhurst has been examined. Fig. 40 Pl. XLIX. Pelobius tardus (Pl. XLIX fig. 40). Median lobe strong, curved, somewhat flattened, produced into blunt barb at tip, with a shallow groove along the ventral side (or the lateral edges turned down ventrally), a membranous tongue (a) covers the basal four-fifths of the groove, the median orifice being covered by this tongue. Lateral lobes large, produced into filament at apex ; articulated to median lobe on dorsal side ,of base. Basal-piece forming a T-shape sclerite, with a large head. No differentiated sac. Family HALIPLIDAE. The form examined is the common European H. fulvus Fabr. Fig. 39 Pl. XLVIII. Haliplus fulvus (Pl. XLVIII fig. 39). Median lobe a flattened curved body, deeply grooved along the ventral side, with a membranous tongue (a) covering the basal three-fourths of groove; the basal part expanded, with lateral lobes articulated to dorsal edge. Lateral lobes asymmetrical, left one short and broad, with hairs on inner surface near distal end ; right lobe longer and narrower, with slender tip, inner surface covered with long fine hairs. Basal-piece forming a wide V-shape sclerite joining lateral lobes across the ventral side. No differentiated sac. 492 Mr. D. Sharp and Mr. F. Muir on the Comparative Family DYTISCIDAE. Forms examined: Dytiscus punctulatus Fabr., and D. marginalis L., England. Ilybius aenescens Th., England. Figs. 37 and 38 Pl. XLVIII. Dytiscus punctulatus (Pl. XLVI figs. 87 and 377). Basal half of median lobe forms a tube, the distal half projecting as four prongs, the dorsal one chitinous, the ventral and lateral ones membranous (fig. 37a, a. 6. b.). The dorsal half of lobe forming a strong chitinous plate, broader and turned down in the middle (c) and bearing hairs at the apex, the basal part being curved upward and expanded ; the ventral half is membranous (m). Lateral lobes large and broad, bearing hairs at the tip and attached to the base of the median lobe on the dorsal side (pa). A thin strut (bp) broad at the end where it supports the membrane between the bases of the lateral lobe, on the ventral side, represents the basal-piece. This functions as a lever to which the muscles for turning the aedeagus are attached. When invaginated the aedeagus rests on its side, but when evaginated it takes a turn and the dorsal becomes ventral. Our figure shows it in its true dorso-ventral position. Sac undifferentiated. Dytiscus marginralis. This only differs in details from D. punctulatus, the median lobe is expanded into a small flattened disc at apex ; the lateral lobes are longer. Tlybius aenescens (Pl. XLVIII fig. 38). Median lobe consisting of a strong, curved, thin sclerite, broad- ened at the base and turned down to form a short groove, the ventral side of this groove being covered by a membranous tongue (a), thus forming a very short tube where the undifferentiated sac opens. Lateral lobes broad at base, flattened and slightly twisted at tips and attached on dorsal side of the base ; the inner dorsal surface being studded with short stout sense-hairs, the rest of inner surface with long fine hairs. Basal-piece (bp) broad at the end where it partly surrounds the base of the median lobe but narrow beyond. This appears to be a more perfect structure than the aedeagus of Dytiscus. The three families, Dytiscidae, Haliplidae, and Pelo- biidae, are closely allied as to the aedeagus, the median lobe being on the same plan, and differing from Carabidae - Anatomy of the Male Genital Tube in Coleoptera. 493 and Cicindelidae. In the latter two families the median lobe is a more or less perfect tube with the median orifice at or near the distal end, and the median foramen at the basal end; in the three other families it forms a chitinous organ, grooved along the ventral surface (or the lateral margin turned down), with a membranous tongue cover- ing the basal part of the groove. There being no differ- entiated sac it is impossible to say how much of the ejaculatory duct is evaginated during coition.* Unfortunately the only Amphizoidae we could procure were females. Family GYRINIDAE. Forms examined: Hnhydrus sp. n., aff. #. atrati, Lita, 4000 ft. Gyrinus natator and urinator, England. Orecto- chilus dispar Walker, Ceylon. Figs. 42, 48 and 43a Pl. XLIX. Gyrinus natator (Pl. XLIX fig. 42). Median lobe slightly flattened and curved; tip truncate ; dorsal and lateral parts chitinous ; median orifice forming a narrow slit on the membranous ventral side near tip; median foramen at base. Lateral lobes flattened horizontally, narrow at base and gradually widening to truncate apex, which bears long hairs; consolidated along ventral basal half and near base on dorsal side. Median lobe articulated to base of lateral lobes on dorsal side. Basal-piece large, forming a large chitinous plate on ventral and lateral sides ; mem- branous on dorsal side; membrane connecting it to lateral lobes large and allowing great movements of parts. No differentiated internal sac. Enhydrus, sp. This is the same type as G. natator, the median lobe being pointed and the lateral lobes pointed on the inner side of a widened tip. Basal-piece large, but connecting membrane not so large as in G. natator, and not allowing so much movement between basal-piece and lateral lobes. No differentiated internal sac. Oretochilus dispar (Pl. XLIX figs. 43 and 43a). Median lobe tubular, drawn to a point on the ventral side of the apex ; median orifice situated on dorsal side of apex; median fora- * F. Netolitzky (Deut. Ent. Zeitschr., 1911, p. 271) has discussed the Adephaga from the point of view of the lateral lobes. TRANS. ENT. SOC. LOND. 1912.—PART III. (DEC.) LL 494 Mr. D. Sharp and Mr. F. Muir on the Comparative men at base. Lateral lobes narrow and bluntly pointed, the distal half bearing fine hairs along edge. JBasal-piece long and narrow. No differentiated internal sac. The aedeagus of the Gyrinidae is of the trilobe type with well-developed basal-piece, and they should not be placed with the Dytiscidae, but near to the Hydrophilidae. The comparatively simple trilobe form and undifferentiated internal sac indicate a form of low specialisation (accom- panied by extreme adaptive characters of the body). In- formation as to the mode of fertilisation in this family is very desirable. Family HYDROPHILIDAE. Forms examined: Hydrophilus (Hydrous of recent authors) piceus L., Europe; H. ater Fabr., Paraguay. Anacaena ovata Reiche, England. Berosus luridus L., and B. signaticollis Charp., Brockenhurst. Laccobius ytenensis Sharp, Brockenhurst. Helophorus aquaticus L., Brocken- hurst. Dactylosternum subdepressum Cast., Panama. Figs. 44-46a Pl. XLIX. Hydrophilus piceus (Pl. XLIX fig. 44). The aedeagus of this insect is the best known of any, as it has been figured and described by many writers. See especially Escherich, Zeitschr. Wiss. Zool. lvii. The’median lobe is well developed, mem- branous, strengthened by three sclerites. A ring-like one (a) sup- ports the median orifice, a thin rod-like one runs down the ventral surface, and a large one (b) covers the dorsal surface ; the latter is narrow at the tip and broadens out basally, where it extends into a pair of median struts (ms), a keel runs down the centre, bifurcates about the middle and the keels continue on to the median struts. The lateral lobes are broad at the base, where they meet both dorsally and ventrally and embrace the base of the median lobe; from the base they taper off to a point at the apex. ‘The basal-piece is formed by a large, shield-shaped sclerite (bp) with its lateral edges turned up, the dorsal side being membranous. When the muscles acting upon the median struts force the median lobe outwards, the fact of it being articulated to lateral lobes (at the point of articula- tion pa) causes it to turn dorsally upon that point, this at the same time forces the lateral lobes apart. This appears to be the action of all the trilobe types in which the lateral arms are free (not con- solidated together) and the median lobe is articulated to the lateral Anatomy of the Male Genital Tube in Coleoptera. 495 lobes. We have not examined one of these forms during copula- tion, but it is most likely that the lateral lobes are used to keep open the external orifice of the female. The internal sac is undifferentiated. Laccobius ytenensis (Pl. XLIX fig. 45). This is a trilobe form. Median lobe chitinous on dorsal side, membranous on ventral side whereon the median orifice is situate. Lateral arms curved, surrounding median lobe. Basal-piece large, membranous on dorsal side. Internal sac undifferentiated. Berosus signaticollis (Pl. XLIX fig. 47). Median lobe thin, tubular, slightly curved and pointed at apex; median orifice on ventral side of apex; median foramen at base; basal edge continued into two curved median struts (ms). Lateral lobes large, consolidated into one piece on the ventral side, forming a flattened trough into which the median lobe falls when at rest ; point of articulation at base. Basal-piece large, forming a flattened trough into which the lateral lobes fall when at rest, the distal edge of the basal-piece being articulated to the middle of the ventral part of the lateral lobes. Internal sac undifferentiated. In B. luridus the median lobe is slender and long, the lateral lobes slender and long and quite free. Basal-piece small and jointed to the lateral lobes in normal manner. Internal sac undifferentiated. The profound difference between these two otherwise allied species is of great interest. Helophorus aquaticus. The median lobe is short, broad at base and bluntly pointed at tip, where the median orifice is situate. Lateral lobes about same length as median lobe, broad at base and bluntly pointed at apex. Basal-piece longer than median lobe, shield-shaped, membranous on dorsal, chitinous on ventral side. Internal sac undifferentiated. Dactylosternum subdepresswm (Pl. XLIX figs. 46, 462). Median lobe flattened, broad at base, pointed at apex, the dorsal aspect being chitinous, the ventral membranous; the median orifice towards the base on ventral aspect (mo). Lateral lobes meeting together at base on ventral face, but wide apart on dorsal ; tapering to a point atapex. Basal-piece small, chitinous all round, but narrow on dorsal aspect, and extending basally on ventral side, there some- what shield-shaped. Internal sac undifferentiated. LL 2 496 Mr. D. Sharp and Mr. F. Muir on the Comparative The Hydrophilidae possess an aedeagus of the trilobe form, with well-developed median and lateral lobes and basal-piece, but with undifferentiated internal sac. This is a generalised type. erosus departs from it furthest in L, signaticollis. Family STAPHYLINIDAE. Forms examined: Gyrophaena pulchella Heer, England. Homalota londinensis Sh.; H. elongatula Gr., and H. pavens Er., Brockenhurst. TZachinus subterraneus L., Brocken- hurst. Zachinoderus grossulus Lec. (? North America, no locality ticket). Ocypus cupreus Rossi, Brockenhurst. Staphylinus cacsareus L., Brockenhurst. Philonthus and Gabrius, numerous species. Creophilus erythrocephalus Fabr., Australia. Quwedius ventralis Ar., Brockenhurst. Pinophilus rectus Sh., and P. mimus Sh., Amazons. Platy- prosopus sp. India. Othius fulvipennis Fabr., and O. melan- ocephalus Grav., Brockenhurst. Xantholinus glabratus Grav., Brockenhurst, and X. phoenicopterus Er., Australia. X. (Lulissus) chalybeus Mann, Brazil. Paederus riparius L., Brockenhurst. Lathrobium brunnipes Fabr., L. fulvipenne Grav., and JZ. boreale Hochh., Brockenhurst, Stenus speculator Lac., Brockenhurst. Osorius sp. near ater Perty, Trinidad. MNodynus leucofasciatus Lew., Japan. Olophrum piceum Gyll., Brockenhurst. Leptochirus edax? loc. dub. Zirophorus bicornis Ol, Amazons. Micropeplus fulvus Er., England. Figs. 61-74 of Plates LII, LIII and LIV are devoted to Staphylinidae. Gyrophaena pulchella (P\. LII figs 61, 61a). Median lobe chitinous, tubular, flattened near tip and twisted and swollen slightly at base ; median orifice narrow, on ventral side near apex ; median foramen at base small. There are two pairs of spines on ventral side close behind median orifice. Lateral lobes large, broad and flattened; inner surface membranous, outer chitinous, and divided into several large sclerites; near apex there is a small articulated lobe bearing two stout hairs. The lateral lobes are attached to median lobe near base on ventral side of median foramen (pa). Internal sac medium size with a long flagellum (fg) arising from apex of sac and passing through median orifice. —— Anatomy of the Male Genital Tube in Coleoptera. 497 This is a highly developed form of the Aleocharid type. The structure is very large in comparison with the size of the insect. Homatota londinensis. Median lobe broad and flattened ; tip on ventral aspect curved downward, and drawn out into a fine point, tipped with a fine pin-head knob. Lateral lobes large and broad; on the lower margin, near base, arises a long curved flattened spine. Sac not examined. Homalota elongatula. Median lobe bulbous at base, membranous on dorsal side, chitinous on ventral, the distal chitinous edge prolonged into a laterally compressed curved tip. The lateral lobes large, flat, and rounded at apex. Homalota pavens. Median lobe swollen at base, chitinous on ventral side, mem- branous on dorsal, distal end not twisted. Lateral lobes large. Sac not examined. 6 c. LZa Tachinus subterraneus (Pl. LII figs. GY, Gle). Median lobe short and bulbous, the ventral aspect formed by a chitinous sclerite jointed at apex, the dorsal by a circular sclerite, with a semi-membranous connection between (m), The median orifice has a dorso-distal position and the median foramen is small with a ventro-medial position. The lateral lobes joined together to near tips, attached to median Jobe near median foramen on posterior (ventral) side. Internal sac large and complex, with a flexible, chitinous sclerite (a) supporting each side; at the distal end there is a large egg-shaped chitinous body (6) with a short tube on one side on which the ejaculatory duct opens. The use of this hollow egg-shaped body we are unable to conjecture. Tachinoderus grossulus, Distal half of median lobe tubular, basal half bulbous; median orifice distal ; median foramen on ventral aspect in median position ; semi-membranous around middle portion of bulbous base. Lateral lobes small, amalgamated to near tip. Internal sac large, with bilobed diverticulum on ventral face, and small chitinous process at apex where the ejaculatory duct opens. 498 Mr. D. Sharp and Mr. F. Muir on the Comparative Ocypus cupreus (Pl. LIT figs. 68, 63a, 630). In this form the median lobe is a strong, chitinous tube with a bulbous base, a semi-chitinous band (m) running round the bulb; the median orifice is distal; the median foramen small and ventral, at the junction of bulb and tube. The lateral lobes are amalgamated and form a broad, slightly-curved plate on the ventral aspect of the median lobe, the tip being slightly cleft. The internal sac large, with four large, round diverticula near base, covered with curved spines ; the dorsal side covered with long strong hairs, the ventral with large curved spines, similar to those on the diverticula ; the apex is drawn out thinner and has two constrictions near the end and the opening of the ejaculatory duct (0) near the tip on the ventral side is supported by two flat chitin sclerites ; a small spine rises just beyond it. The sac shown in the figure is drawn from a specimen taken in copula ; it had the position figured. Creophilus erythrocephalus, has a median lobe somewhat like O. cwpreus, but the lateral lobes form a single broad prong on the ventral face, Internal sac medium size with a short curved flagellum arising from apex. Quedius ; has a similar form of median lobe to Ocypus, and the lateral lobes form a single piece on its ventral side. In Q. ventralis (Pl. LII fig. 64) the internal sac is figured evaginated. In Q. brevicollis the internal sac has a pair of small diverticula near apex and the opening of the ejaculatory duct below them, also a larger pointed pair on the dorso-lateral part of the middle, and a round diverticulum on the ventral side near base, covered with semi-chitinous pegs. Q. vexans (of our British collections) has median and lateral lobes of the same type, the internal sac being swollen at base and thin for the distal two-thirds ; a pair of blunt diverticula arise from the side near the middle, and a backward-pointing one nearer the base on a median-ventral line. Pinophilus rectus (Pl. LIV figs. 71, 717). Median lobe large, bulbous at base, with semi-membranous strip (m) running across to near apex; apex with dorsal edge projecting beyond ventral; median orifice on ventral side of apex ; median foramen small, on ventral side about one-fourth from base. Lateral lobes thin narrow strips, articulated to median lobe on ventral edge of median foramen. Internal sac about 15 mm. long, thin, tubular, coiled up in median lobe when invaginated. Arising from apex of sac is a fine chitinous flagellum as long as the sac, with the opening of the ejaculatory duct at its tip. At the base of the Anatomy of the Male Genital Tube in Coleoptera. 499 sac are three irregular chitin plates (b) with a narrow strip of chitin (a) running some way along the sac. These appear to form guides for the flagellum. P. mimus has a similar sac and flagellum which make ten complete coils in the median lobe, like a coil of rope, and measure 20 mm. In Pinophilus where there is an enormously long sac and flagellum, coiled up within the median lobe, it is not likely that the sac is evaginated, but the flagellum is thrust out and the basal part of the sac folded up like a concertina bellows; nor is it likely that the whole of the long flagellum is everted, but the muscles acting upon the coils cause it to operate like a coiled spring, the distal end being thus thrust out and retracted when the muscular pressure is relaxed. Othius fulvipennis (Pl. LIII fig. 65). Medium lobe bulbous with ventral distal edge projecting ; median orifice dorso-distal, median foramen small, ventro-medianal ; a semi- membranous band running round bulbous part of median lobe. Lateral lobes thin, separate, attached to median lobe on ventral edge of median foramen. Internal sac large, apex forming two diverticula ; on the larger diverticulum the ejaculatory duct opens; a small bilobed diverticulum on dorsal side and a pair of large diverticula on ventral side ; between these last processes and the base are two pairs of curved chitinous spines. Othius melanocephalus (Pl. LIII fig. 66). Very much like O. fulvipennis, but the internal sac differs greatly ; on each side near apex is a fine long diverticulum (a). Xantholinus glabratus (Pl. LILI figs. 67, 67a, 670). In this species the bulbous median lobe is of an extreme form, being egg-shape, with a small membranous distal portion to which the greatly reduced lateral lobes are attached. The median lobe is formed of dorsal and ventral sclerites, round, and connected by a semi-membranous band (m); the median orifice (mo) is at the distal end, and the median foramen (m/f) slightly in front (or basal) on the ventral face. These two openings are separated only by a chitinous plate (a) formed by the basal part of the lateral lobes which are extremely reduced. The internal sac is three times the length of the median lobe, tubular, and studded with large teeth, curved basally, 500 Mr. D. Sharp and Mr. F. Muir on the Comparative A less modified form is found in Xantholinus (Hulissus) chalybeus (Pl. LILI figs. 68, 68a) from Brazil ; in which the distal end of the median lobe is short and tubular, drawn out into a point on the ventral side, the median foramen being situate in the ventral chitinous sclerite at the base of the short tubular distal end, X. phoenicopterus is also less modified than X. glabratus, the lateral lobe being much larger and the median foramen on the ventral sclerite, Paederus riparius (Pl. LIIT figs. 69, 69a). The median lobe broad, slightly flattened and slightly bulbous at base, the dorsal distal margin projecting beyond the ventral, the median orifice being on ventral face beneath this projection ; the median foramen small, near base slightly dorsal. The lateral lobes broad, flattened, with curved pointed apices projecting beyond end of median lobe, closely applied to sides of it, and attached to it near the ventral edge of median foramen. Internal sac with large curved spine (a) at base. Apex of sac not examined. Lathrobiwm brunnipes. The median lobe bulbous and membranous, except on the ventral basal part which is chitinous ; median orifice at tip ; median foramen small, about the middle. Lateral lobes consolidated into a single body, broad at base and narrow at apex where there are two small points; a groove runs along the ventral side. They form the strongest part of the aedeagus and are consolidated to the ventral face of the median lobe from the edge of the median foramen to the tip. Internal sac not examined. L. fulvipenne is of the same type as L. brunnipes, but the left lateral lobe appears to be absent and the right is large and projects as a curved spine ; there is also a chitinous support on the dorsal side of the median orifice. L. boreale. The same type as L. brunnipes, the lateral lobes being consolidated into a single piece, the tip being pointed and turned down like a small hook, the median ventral line being keeled, not grooved. The dorsal margin of the median orifice is supported by a small chitin plate and a strong chitin piece with two hooks at the end projects from the basal part of the internal sac. On each side of the internal sac, near the base, is a patch of chitinous flat scales, prolonged into prongs on the basal edge. When the sac is evaginated the two-hooked piece on the dorsal side of the base turns over and Anatomy of the Male Genital Tube in Coleoptera. 501 points basally. The aedeagus in Lathrobiwm is extremely irregular and asymmetrical in structure. Stenus speculator (Pl. III figs. 70, 70a). Median and lateral lobes on same plan as Paederus riparius. Internal sac large, with two chitin strips (a). These chitin strips are continuations of the chitin of the ventral surface of the median lobe. Osorius sp. (Pl. LIV fig. 72) from Trinidad, apparently has the lateral arms entirely missing, or reduced to a narrow, small band slightly distal of the median foramen on the ventral side (Il), The median lobe is bulbous with the dorsal side semi-membranous and the ventral distal edge pointed. The internal sac is large with two diverticula near base, one bearing short hairs on the tip, and a large curved diverticulum at end, ventral of the opening of ejaculatory duct. Nodynus lewcofasciatus, Median lobe bulbous at base, chitinous on ventral side and drawn out distally to a point, the dorsal side being membranous ; median orifice at distal end on dorsal side; the median foramen small, on ventral side and about the middle. Lateral lobes fairly broad, pressed against sides of the median lobe and projecting slightly beyond tip, attached to median lobe on ventral side of edge of median foramen. Internal sac without chitinous armature. This is very Silphid-like, but the absence of the basal-piece separates it from that group. Olophrum piceum is very like Nodynus, the lateral lobes being flattened and curved. Internal sac long, flattened and coiled up in the median lobe ; its surface covered with hair-like scales. Leptochirus, sp. Median lobe tubular, curved ventrally near the base ; semi- chitinous on dorso-basal part. Median orifice on dorsal side of tip ; median foramen small, near base on ventral isde. Lateral lobes small, about one-fifth the length of the median lobe. Internal sac large, but not examined. Zirophorus bicornis (Pl. LIV fig. 73). Has a thin, slightly flattened median lobe, strongly chitinised and curved at the base, and semichitinous along the dorsal basal part (m). The lateral lobes are articulated to the curved base and consist of narrow lobes free along their whole length. Median orifice at distal end, median foramen at base. Internal sac short and without armature, 502. Mr. D. Sharp and Mr. F. Muir on the Comparative Micropeplus fulvus (Pl. LIV fig. 74). This is a Staphylinid type, the median lobe being large and bulbous at the base; the median orifice at the apex large, the median foramen small and one-fourth from base on ventral side. The lateral lobes are so completely amalgamated to the median lobe that it is very difficult to distinguish them, but they are of fair size and lie along the ventro-lateral portion of the median lobe, The internal sac is large, complex, covered with small chitinous spines and supported by chitinous patches, It is among the Staphylinidae that we have found the greatest modification of a single type. In this family the internal sac reaches a high state of specialisation and the modification of the median lobe for the evagination of the sac by blood-pressure is carried to perfection. This is brought about by modifying the tubular median lobe into a bulb having chitinisations on the dorsal and ventral aspects, with a band of membrane between, so that the dorsal and ventral sclerites can be brought together by muscular contractions and so exert pressure of a fluid on the sac and turn it out. The Staphylinidae are distinguished from the Silphidae by the absence of a basal-piece. Since our paper was written Dr. L. Weber of Cassel has published a very valuable paper on the male genitalia of Staphylinidae (Festschr. Ver. Cassel, 1911). We are, however, not pre- pared to accept his interpretation of the very abnormal genus Habrocerus, as to which he himself speaks with considerable diffidence. Family SILPHIDAE (= families Si/phidae, Liodidae, and Clambidae, Reitter). Forms examined: Stlpha (Phosphuga) atrata L., Eng- land. S. obscwra L., England. 8S. japonica Motsch., Japan. S.? analis Chevr., Panama. Necrodes osculans Vig., Woodlark Island. Necrophorus mortuorwm Fabr., England. Astagobius angustatus Schm., Carniola. Ba- thyscia (sp. not in Brit. Mus.), Piedmont. Liodes (Anisotoma of certain authors) humeralis Fabr., England. Clambus minutus St., England. Figs. 48-54, Plates XLIX and L, are devoted to this group. Anatomy of the Male Genital Tube in Coleoptera. 503 Silpha atrata (Pl. XLIX fig. 48). Median lobe flattened, broad, with ventral side chitinous and dorsal membranous ; median orifice at distal end ; median foramen small, situate in the basal part of the ventral chitinous plate. Lateral lobes broad at base, tapering to rounded point at apex. A thin ring of chitin runs over the base of median lobe (bp) and joins the bases of the lateral lobes; this represents the basal-piece. Internal sac large, rounded at the apex, with three large, round diverticula at base (b), covered with long, fine hairs, thickest on the dorso-basal surface. The median lobe is not consolidated to the basal-piece and can be dissected away. The figure shows the apex of sac collapsed, the broken lines (c) show the more normal shape. Sulpha obscura (Pl. Li figs. 49, 49a). Median lobe large, extending beyond the basal-piece ; the ventral and lateral faces of the distal half chitinous, the dorsal side and all the basal half membranous, except a small strip of chitin (a) extend- ing from the median foramen (mf) towards the base, The median orifice on dorsal side of tip ; the median foramen small, placed about middle of ventral side. Lateral lobes fairly broad, curved at tips and bearing a small knob, they are pressed closely to the latero- ventral surface of the distal half of the median lobe. The basal- piece is ringlike (bp). Internal sac large ; details not examined, Silpha japonica. Of the same type as S. atrata, The internal sac is flattened horizontally and constricted in the middle, the dorsal surface is covered with long, silky hairs. Silpha analis (Pl. L fig. 50). Though probably a different genus this is similar to the various species we have already remarked on. The basal-piece is of rather larger extent. Internal sac large with a large curved prong (a) on each side near the base, basal part covered with short hairs, distal part with granulated surface. Necrodes osculans, The aedeagus is of the Silpha obscura type. The median lobe broad, with distal half chitinous, especially on the ventral aspect, the ventral half membranous ; the median orifice dorso-distal, and the median foramen ventro-medial. The lateral lobes each broad 504 Mr. D. Sharp and Mr. F. Muir on the Comparative at base, the apex slightly curved. The basal-piece consists of two small narrow sclerites, attached to the base of the lateral lobes, but they do not meet on the dorsal side. Necrophorus mortuorum (Pl. L fig. 51). Median lobe chitinous on ventral and lateral aspects, membranous on dorsal aspect ; median orifice large, on dorsal aspect of apex ; median foramen small, on ventral aspect about one-fourth from base. Lateral lobes broad at base, tapering to blunt point, bearing several hairs, Basal-piece (bp) slender and ring-shaped. Internal sac large, but details not examined. Astagobius angustatus. The median lobe large, slightly flattened and curved ; the median orifice on the ventral face of apex, the dorsal edge being pointed ; median foramen large, at base. Lateral lobes long and thin ; basal- piece formed by a small curved sclerite on ventral face, but not meeting on dorsal. Internal sac large, armature not observed. Bathyscia, sp. (Pl. L figs. 52, 52a). Median lobe tubular, slightly flattened towards apex on dorsal face where it graduates to a point ; median orifice at apex on dorsal face ; median foramen (mf) at base, as large as the diameter of the median lobe, the edge being strengthened by a thickening of the chitin (a). The tegmen consists of a broad ring-shaped basal- piece (bp) with a pair of thin lateral lobes lying along each side of the median lobe, the basal-piece being slightly posterior of the base of the median lobe. Internal sac large, extending through the median foramen, Arising from the apex of the sac is a short, stout flagellum (c), along which the ejaculatory duct continues and opens at its tip. The dorsal face of this flagellum is chitinous (a) and broadened at the base where the corners articulate with a Y-shaped (y) support (Jeannel’s Y-piece) ; the ventral face of the flagellum is membranous, except at the tip where the chitin forms a short fine tube.* Fig. 52a represents the internal flagellum (c of fig, 52) on a much higher scale of magnification. Liodes humeralis (Pl. L figs. 58, 53a, 53b) is of the same type as Bathyscia. 'The median lobe is chitinous, strongly bent at the basal third, swollen at base and pointed at apex; the median orifice is at apex on ventral face; the median foramen at base, and as large as the enlarged base of median lobe. The tegmen consists of a * On this group reference may be made to an important memoir by Jeannel, Arch. Zool. exp. v, 1910. Anatomy of the Male Genital Tube in Coleoptera. 505 ring-like basal-piece, broader on dorsal than on ventral aspect, with a pair of narrow, pointed lateral lobes pressed close to the sides of the median lobe. The internal sac not large, but with complex armature at apex (53a, 53b). A flat, curved median chitin-piece (0) is attached to the internal sac by a large chitin knob (c) through which the ejaculatory duct runs and opens on the end of the median piece ; a chitin plate (d) with a second chitin knob (e) gives it greater support. To each side of the chitin knob (c) is attached a flattened pointed process, thickened at its base at the point of attachment, one is slightly longer than the other. Clambus minutus (Pl. L fig. 54). Median lobe a thin, partly flattened, tube, with the dorsal distal part drawn out into a curved process hooked at the tip, the ventral distal part into a semi-membranous tongue. The lateral lobes are amalgamated for two-thirds of their length and form a broad shallow plate with the distal third forming unequal points, bearing a couple of stout spines. The basal-piece ring-shape (bp). Internal sac not examined. Among the Silphidae s. 1. that we have examined there are three distinct types of aedeagus. The first is repre- sented by Sil/pha, in which the median foramen is small, the median lobe collapsible on the dorsal aspect and forms a collapsible bulb by means of which the internal sac is evaginated by fluid-pressure, and the sac bears no chitinous armature. In the second the median foramen is large, and the median lobe is not collapsible and does not function as a bulb for the evagination of the sac, and the sac bears chitinous armatures. The third type has the lateral lobes amalgamated to- gether to form one piece, and the median lobe is tubular and not collapsible. These characters do not quite agree with the divisions into families of the Silphid allies. As, however, the recent authorities are not in accord on this point, and as we have studied a very small percentage of the known forms, we have treated the assemblage as one family. But we hope our doing this will not be interpreted as supporting either one view or the other. The Silphid type approaches the Staphylinid type, but the presence of a reduced basal-piece serves to distinguish the two. 506 Mr. D. Sharp and Mr. F. Muir on the Comparative Family LEPTINIDAE. Form examined: Leptinus testaceus Miill., Brockenhurst. L, testaceus (Pl. LI figs. 55, 55). Median lobe large, chitinous on dorsal aspect, where it is drawn out into a point and on the sides, semi-membranous on the ventral aspect ; median orifice on the ventral aspect of the distal end (mo) ; median foramen large at basal end, and proceeding somewhat along dorsal side (b). Lateral lobes thin narrow bodies lying along the dorso-lateral parts of the median lobe and projecting somewhat beyond its tip. Basal-piece well developed, forming a ring through the base of which the median lobe passes and projects beyond, basally. Point of articulation on dorsal side. This basal-piece is distinct but of a semi-chitinous nature. Internal sac large, project- ing through the median foramen; it bears a patch of hairs near its apex, and about the middle a long slender chitin rod (a) attached to the sac by a broad square base; the ejaculatory duct does not pass through it. This differs but little from certain Silphidae. Family PLATYPSYLLIDAE. Form examined: Platypsylla castoris Rits., N. America. P. castoris (Pl. LX XVII fig. 229). This comes near to Leptinus from which it differs only in details. Median lobe tubular, pointed at apex and greatly enlarged on basal two-fifths; median orifice on ventral face near apex; median foramen large at base. Tegmen consisting of a basal-piece surround- ing the median lobe anterior to the basal enlargement, and a pair of narrow lateral lobes situate on the dorsal face. Internal sac smaller than in Leptinws and not passing through the median foramen when at rest, covered with hairs and flattened pointed scales; a thin flagellum arises from the apex. We are indebted to Mr. E. A. Schwarz for the opportunity of examining this interesting species. Family SCAPHIDIIDAE. Form examined: Scaphidiwm quadrimaculatum Ol, Brockenhurst. S. quadrimaculatum (Pl. LIV fig. 76). This is a characteristic Staphylinid type. Median lobe with distal half forming a wide tube, basal half bulbous, with a membranous Anatomy of the Male Genital Tube in Coleoptera. 507 band round the bulb (m) ; median orifice large, at distal end, with ventral edge projecting beyond dorsal; median foramen small on ventral face, about one-third from base, Lateral lobes attached to median lobe on ventral aspect, at the ventral edge of the median foramen. Internal sac large, with patches of short hairs ; details not studied. Family TRICHOPTERYGIDAE. Form examined: TZ'richopteryx grandicollis Mann., Eng- land, and some others. T. grandicollis (Pl. LX XVII figs. 231 and 231¢). The aedeagus consists of a short tube with a pair of hooked struts on the ventral side of the base, the median orifice large, with the ventral edge produced into a blunt point. Internal sac large, bearing small spines and a small chitin-plate (a) on the dorsal face and some chitinisation on the ventral (b) which we have not definitely made out. The position of the opening of the duct on the sac was not observed. We could find no trace of tegmen. A small plate with a central strut exists below the aedeagus, but it appears to be a body selerite and not the tegmen. At present we are unable to associate this with any other form. Luryptilium marginatum has the organ longer, with the ventral margin of the median orifice projecting, pointed, and turned down. Mr. H. Britten has submitted to us for examination dissections of 7. grandicollis, T. thorica, T’. bovina, T. brevis, EHuryptiium marginatum, Ptiliolum spencei and an un- identified species. These are each and all easily recog- nised by the aedeagus. Family CORYLOPHIDAE. Forms examined: Saciwm politwm (coll. Matthews), hab.? Corylophus cassidioides Marsh., England. Fig. 75 Pl. LIV. Sacium politum (Pl. LIV figs. 75, 75a). Median lobe a large flattened tube, the median orifice at the distal end, the ventral edge extending beyond the dorsal and pointed; the median foramen very small at the basal end. Tegmen forming a 508 Mr. D. Sharp and Mr. F. Muir on the Comparative “ring-piece,” the cap (a) or lateral lobes forming a wide curved plate slightly emarginate; the basal-piece forming a large shield-shaped plate with a deep keel down the centre (b). Internal sac large, with complex armature. Corylophus cassidioides is of the same type. At present we cannot directly connect this to any other type; the small median foramen with the internal sac contained in the median lobe is unique among the “ring” forms, where it is the rule to have a large median foramen and the internal sac passing through it, when not evaginated. Family SCYDMAENIDAE. Forms examined: Stenichnus collaris Miill., England. Humicrus (recently Scydmaenus) tarsatus Miill., England. Leptomastax coquerelt Fairm., Corfu. Figs. 56, 56a, 6 and ¢, 57 Pl. LI. Stenichnus collaris (Pl. LI figs. 56, 56a, 56, 56ce). The distal portion of the median lobe forms a short thick irregular tube ; the basal part being curved under and prolonged into a flattened narrow process (f), a band of membrane (m) connecting the two portions ; the median orifice is large, at the distal end ; the median foramen small, situate on the dorsal face about two-thirds down the tubular distal end of the median lobe. Lateral lobes narrow flat pro- cesses, attached to the median lobe at the dorsal edge of the median foramen. Internal sac short but very complex (56c). On the dorsal face there is a membranous surface bearing a pair of keels studded with chitinous teeth (q) which converge together in the centre above the opening of the ejaculatory duct ; on the ventral half is a broad chitinous plate somewhat shoe-shaped in lateral view (a and )), bearing a pair of small toothed processes (h). We would like to call attention to the great importance of recognising the mobility of the mternal sac and con- comitantly the variation in the position of the sac armature, especially when it closes the median orifice. Unless this is understood the shape of the aedeagus will appear to vary greatly in certain species. In the figures we give, fig. 56 shows a side view with sac invaginated, 56) shows the sac partly evaginated, and 56c with it entirely evaginated, or nearly so; 56a gives a ventral view of 560. Anatomy of the Male Genital Tube in Coleoptera. 509 Humicrus tarsatus (Pl. LVII fig. 57). Median lobe tubular, slightly curved, with large median orifice at distal end and small median foramen at base. Lateral lobes large, broad and closely pressed to sides of median lobe; they extend beyond the end of the median lobe where the tips are consolidated into a single point, entirely enveloping the ventro-apical portion of the median lobe. Although the lateral lobes are pressed very closely to the median lobe, yet they are not consolidated thereto, and can be parted without damage. Internal sac small with a curved chitinous process (a) bearing the opening of the ejaculatory duct at its tip. Leptomastax coquerelt. Median lobe similar to Ewmicrus tarsatus; the lateral lobes are broad and flat but do not meet and become consolidated at their tips. Internal sac small, with a chitinous process ending in a short flagellum on which the ejaculatory duct opens. The family Scydmaenidae exhibit a great diversity of form, but all appear to be of one type. Median lobe more or less tubular with a large median orifice and a small median foramen more or less inclined to the dorsal face. The lateral lobes articulated to the base of the median lobe on the dorsal face of the median foramen. Internal sac bearing armature. The point of articulation being on the dorsal side of the median foramen distinguishes this family from the Staphylinidae wherein the point of articulation is on the ventral side. The distinguished French entomologist, M. de Peyerim- hoff, has published a memoir on the male structures of Scydmaenidae, in which he expresses the opinion that the structures are in some species variable. We would point to our remarks under Stenichnus collavis as possibly explaining the discrepancies he remarks on. Family PSELAPHIDAE. Forms examined: Sagola sp. (not in Brit. Mus.), New Zealand. Trichonyx sulcicollis Reich., Brockenhurst. Bry- axis impresst Panz., and B. jwncorum Leach, Brockenhurst. Physa inflata Sharp, New Zealand. Palimbolus sp. (not in Brit. Mus.), New South Wales. Figs. 58, 59, 60 and 230 Pls. LI and LII. TRANS, ENT. SOC. LOND. 1912.—PARY III. (DEC.) MM 510 Mr. D. Sharp and Mr. F. Muir on the Comparative Sagola sp. (Pl. LII fig. 59). Median lobe long, slender, tubular and slightly curved, the median orifice at apex, the ventral edge projecting beyond the dorsal. Lateral lobes large, flattened laterally and lying on each side of median lobe, with their base in intimate union with the base of the median lobe. The piece we call basal-piece (bp) appears to belong to the lateral lobes and not to be a true basal- piece, but this point is obscure. Internal sac undifferentiated. Trichonyx suleicollis. Median lobe bulbous with circular, membranous patch on dorsal face; median orifice at distal end, closed by a chitin plate which is attached at the base of the internal sac; this plate moves when the sac is evaginated ; median foramen small, about two-thirds from base. Lateral lobes short, flattened, applied closely to the ventral face of the distal end of the median lobe. Internal sac large, armed with strong chitinous plates. Bryaxis impressa (Pl. LXXVII figs. 230, 230a and 0). This appears to be much on the same plan as Sugola, but the lateral lobes in their basal part are consolidated to the sides of the median lobe, and their more median portions apparently meet, while their outer portions remain free, divergent and pointed. If a section be taken through the middle of the aedeagus it should include three lumens, in the middle that of the median lobe (d of fig. 230b) and another on each side, c, the lumen of the lateral lobe. Internal sac undifferentiated. There is considerable difficulty in the interpre- tation and delineation of this structure, as regards the distal portions of the median strips of the lateral lobe. In the figures 230 and 230a it is assumed that they pass beyond the median orifice and then meet at the point a. Bryaxis guncorum. The aedeagus is on the same plan as B. impressa, but is shorter and more bulbous; the lateral lobes are consolidated to the median lobe. Physa inflata (Pl. LI fig. 58). Median lobe bulbous, ventral and dorsal walls chitinous with a membranous band (m) around the middle, median foramen small, ventral and nearly median. The lateral lobes hard to distinguish from median lobe but appear to be the two pointed sclerites on each side of median orifice (I), but it is possible that the median sclerite (a) on the ventral distal part of the median lobe represents Anatomy of the Male Genital Tuhe in Coleoptera. 511 the consolidated and reduced lateral lobes. Internal sac large, swollen towards the apex where it is produced into two small diverticula, between which the ejaculatory duct opens, the apical dorsal part bearing spines, and a large spine on each side a third from the base. Palimbolus sp. (Pl. LII fig. 60). Median lobe bulbous with right edge of median orifice prolonged into point; except fora batch of membrane on dorsal side (m) the median lobe is chitinous; median foramen small, on ventral face. Lateral lobes small, subcircular bodies applied closely to median lobe slightly posterior of the median foramen, Internal sac well developed with two chitin rods (a) supporting the ventral surface and forming two rounded projections beneath the opening of the ejaculatory duct. The few forms of Pselaphidae that we have examined show very interesting differences which future investiga- tion will probably show to be characteristic of distinct groups, unless connecting forms should be found. The type is closely allied to the Staphylinid. The possibility of Bryaxis having a true basal-piece included in the aedeagus requires investigation, as the possession of such a structure would prevent their being regarded as direct offshoots of the Staphylinidae. Family SPHAERITIDAE. Form examined: Sphaerites glabratus Fabr., Scotland. Fig. 78 Pl. LV. Sphaerites glabratus (Pl. LV figs. 78, 78a). Median lobe thin, only the tip visible; median orifice at tip. Lateral lobes large, consolidated together for the greater part of their length on the ventral, and for half their length on the dorsal face, thus forming a tube in which the median lobe lies. Basal- piece small and asymmetrical, the chitinisation forming a broad circular band. Internal sac undifferentiated. This is very like Syntelia. Family SYNTELIIDAE. | Form examined: Syntelia histeroides, Japan. Syntelia histeroides (Pl. LV figs. 77, 77a). Median lobe well developed, long, curved, tubular, with a pair of median struts, Lateral lobes very long and curved towards their MM 2 512 Mr. D. Sharp and Mr. F. Muir on the Comparative pointed apices, consolidated together for the greater part of their length. Basal-piece small, symmetrical, with the opening on the ventral (?) face. This comes near to Sphaerites. Family NIPONIIDAE. Form examined: Niponius canalicollis, Japan. Fig. 82 Pl. LY. Niponius canalicollis (Pl. LV figs. 82, 82a). Median lobe tubular, slender and long ; lateral lobes longer than median lobe and enveloping them. Basal-piece forming a long tube, constricted near its base and bent. Internal sac undifferentiated. This form of aedeagus is nearest to Syntelia but differs in having the tubular basal-piece long, a character in itself not of family importance. Family HISTERIDAE. Forms examined: ister cadaverinus Hoffm., England. Pachylister chinensis Quens., China. Mucrolister maximus OL, Africa. Oxysternus maximus L., Guiana. Hololepta elongata Er., Andaman Islands. H. arcifera Mars., Cameroons. Saprinus nitidulus Fabr., England. Teretri- osoma stebbingt Lewis, India. Figs. 79, 80 and 81, Pl. LV, relate to Histeridae. Hister cadaverinus (P\. LY figs. 79, 79a). Median lobe well developed, chitinous, slightly curved, with a large flange running round the lateral and distal edges of the apical half (a), forming a cavity in which the apical armature lies when the median lobe is at rest. This median armature is a pair of two-pronged structures, amalgamated at their bases and articu- lated to the base of the median lobe; when the median lobe is withdrawn between the lateral lobes at rest, the armature lies in the cavity, but when it is thrust out the armature turns back. There is a pair of short median struts. Tegmen consisting of a small basal-piece with very large lateral lobes amalgamated on their ventral side to the tip, and on the dorsal side along the basal half. Internal sac undifferentiated. Macrolister maxims. A figure is given of this with the median lobe erected (Pl. LV fig. 80). Anatomy of the Male Genital Tube in Coleoptera. 513 Oxysternus maximus. Median lobe rod-like, dilated at the tip into a cleaver-shaped process. Basal-piece moderately long, slightly asymmetrical, with a large membranous area on one aspect, just anterior to its junction with the lateral lobes. Lateral lobes very long, coalesced on their basal portions to form a very hard tube, the apical two-fifths forming a half tube, or trough, at the basal portion of which is the articulation of the median lobe. The rod-like, very hard median lobe renders it pretty certain that the sac remains un- differentiated. The aedeagus is here a beautiful structure with very solid chitinisation. Hololepta elongata (Pl. LV figs. 81, 81a). The aedeagus is flattened and thin, the basal-piece more than two-thirds the length of the lateral lobes; the lateral lobes amal- gamated along the dorsal surface to the tip and along the ventral surface for the basal two-thirds. The median lobe is greatly reduced. Saprinus nitidulus. Median lobe small, only the tip visible. Lateral lobes very large, consolidated together along their entire length, with the tips slightly flattened and turned down; this forms a complete tube with an-opening at the tip on the dorsal side. Basal-piece very small, asymmetrical. Internal sac small, apparently not differentiated. Teretriosoma stebbingi. We are indebted to Mr. Lewis for the opportunity of examining this rare and interesting Histerid. The individual was in a very decayed con- dition and the preparation was not very successful, but it shows that this form departs from the other Histeridae we have examined by the shape of the lateral lobes, which are flattened divergent laminae. Their conjunc- tion with the basal-piece seems to be more intimate than usual, The four families Misteridae, Synteliidae, Sphaeritidae and Nipontidae are so closely related by the aedeagus, that they might form one family, in which the Histeridae would include the higher developments. Its characteristics are the existence of a basal sclerite having no power of move- ment over the median lobe, and extremely large lateral lobes more or less amalgamated to forma tube. The type is extremely different from Staphylinidae. But the approximation to the Byrrhidae is clear. 514 Mr, D. Sharp and Mr. F. Muir on the Comparative Family PHALACRIDAE. Forms examined: Phalacrus grossus Er, Spain. Lito- librus obesus Sharp, Panama. Olibrus corticalis Panz., England. Figs. 83 and 84 Pl. LVI are Phalacridae. Phalacrus grossus (Pl. LXI figs. 83, 83a). Median lobe broad and flattened ; median orifice on dorsal face at apex; median foramen large. Tegmen forming a ring-piece. The “cap-piece” formed of the two flattened lateral lobes consoli- dated on the dorsal side to near their apices, and a large flat plate, turned down along the lateral edges, the basal corners meeting together on the ventral side of the median lobe, where the ring is asymmetrical. Internal sac large and complex. There is a pair of long tubular glands which open on the apex of the sac, one on each side of the opening of the ejaculatory duct. As our specimens were dried we could not examine the testes to see if these glands were extra, or if there were the usual ones having an abnormal opening. In Olibris corticalis these glands are not present in this position. Litolibrus obesus (Pl. LVI fig. 84). Median lobe broad and flattened, slightly bent near the base where a flange (a) runs along the dorsal face ; median orifice on dorsal aspect at tip; median foramen large, on ventral side of base. Tegmen forming ring-piece. Lateral lobes small, consoli- dated together and forming a pointed, flattened plate bearing a pair of small curved hooks ; basal-piece long and narrow on dorsal side, broadened at the base where it encircles the median lobe, having two deep emarginations causing the median central portion (6) to project as a tongue, Internal sac large, bearing a pair of double claws and a pair of small plates, as armature. Family MONOTOMIDAE. Form examined: Monotoma conicicollis Guér., England. Fig. 85 Pl. LVI. Monotoma conicicollis (Pl. LVI figs. 85, 85a). Median lobe short, broad, flattened, and slightly curved; median orifice at tip, the dorsal edge projecting beyond the ventral and pointed ; median foramen at base and of large size. From the ventral edge of the median foramen proceed two long struts (ms). Anatomy of the Male Genital Tube in Coleoptera, 515 Tegmen (fig. 85a) forming a ring-piece, the dorsal part being a hood- shaped body, with a thin piece proceeding from each basal corner and consolidating on ventral side of median lobe. Internal sac very large, bearing armature near base (b) and towards apex (a). Family NITIDULIDAE. Forms examined: Psilotus atratus Reitt., Chiriqui. Cychramus luteus Fabr., England. Jps (Glischrochilus of various authors) japonius Motsch., Japan. Figs. 87 and 88 Pl. LVI. Psilotus atratus (Pl. LVI fig. 87). Median lobe tubular, broad and flat, with single median strut. Tegmen forming a large broad curved plate or hood, on dorsal face, with a small dorsal median projection (a) from base, the basal corners meeting and consolidating on ventral side of median lobe. Internal sac large, the opening of ejaculatory duct at apex, where it is supported by two chitin rods consolidated together at tip (b) round the duct opening. Ips japonius (Pl. LVI fig. 88) is of the same type as P. atratus; and so is Cychramus, the “ hood’ being much larger than the median lobe, ) The family Monotomidae comes near to these forms, as also does Helotidae. On the other hand, Rhizophagus does not belong to Nitidulidae. Whether it can be satisfactorily placed in Cucuwjidae (where we have treated of it, cf. fig. 101), can only be determined by a much more extensive survey of the Cucujidae than we have made. Family BYTURIDAE. Form examined: Bytwrus tomentosus Fabr., England. Fig. 86 Pl. LVI. Byturus tomentosus (Pl, LVI fig. 86). Median lobe long, ‘slender, and pointed; median orifice at tip on dorsal face; median foramen at base. Tegmen forming a close- fitting sheath, the distal half chitinous, the basal half membranous, with a strip of chitin supporting each side (a); and a Y-piece with a long stalk (b) supporting the ventral aspect. Internal sac undifferentiated, This type is similar to Trogositidae. 516 Mr. D. Sharp and Mr. F. Muir on the Comparative Family TROGOSITIDAE (or Ostomidae, or Temno- chilidae). Forms examined: TZemmnochila virescens Fabr., Mexico. Alindria grandis Serv., Africa. Leperina, sp. n.? aff. adustae Pase., Australia. Thymalus limbatus Fabr., Brockenhurst. Figs. 89 and 90 Pls. LVI and LVII. Temnochila virescens (Pl. LVI figs. 89, 89a). Median lobe long, flattened laterally, formed by a trough-shaped chitin plate (a) on ventral aspectand membrane on dorsal aspect (b), with a chitin strut round median orifice at distal end (c). Tegmen formed into a sheath ; lateral lobes distinct and only amalgamated at base ; basal-piece large and tubular, chitinous on dorsal and ventral aspects, membranous on sides. Internal sac undifferentiated. Alindria grandis is of the same type, but the division between lateral lobes and the basal-piece is obliterated. Thymalus limbatus (Pl. LVII figs. 90, 90a). Median lobe long, straight, flattened laterally. Tegmen forming a sheath with lateral lobes consolidated together on the ventral aspect, basal-piece long, tubular, with a strong strut on the dorsal aspect at base (a). Leperina aff. adustae is of the same type but has the lateral lobes free. It is possible that this type is a development of a trilobe type through such a form as Awlonium. Byturus belongs near this family. Family COLYDIIDAE. Forms examined: Hnarsus bakewelli Pase., New Zealand. Tarphiomimus indentatus Woll., New Zealand. Auloniwm bidentatum Fabr., Guatemala. Deretaphrus ignavus Pasc., Australia. Cerylon histeroides Fabr., England. Figs. 91-95 of Pl. LVII relate to the above-named forms. Enarsus bakewelli (Pl. LVII figs. 92, 92a, 920). Median lobe nearly as long as tegmen, chitinous on dorsal and lateral aspects, membranous on ventral (a); median orifice on ventral aspect near apex. ‘Tegmen consists of a large basal-piece formed of a ventrally-placed sclerite, the dorsal aspect membranous, and a pair of Anatomy of the Male Genital Tube in Coleoptera. 517 lateral lobes joined together on their ventral aspects and forming a large plate ; the median distal portion of the plate projecting between the distal ends of the lateral lobes as a free process, truncate at tip (b). No differentiated internal sac. In this species there is a distinct abdominal plate between the anus and aedeagus (lv), which we think must be the last ventral sclerite of the body. Tarphiomimus indentatus is of a similar type (Pl. LVIT fig. 98). Aulonium bidentatum (Pl. LVIT figs. 91, 91a). Median lobe large, somewhat flattened ; median orifice near tip on ventral face. Tegmen formed of a large basal-piece, chitinous on ventral and membranous on dorsal aspect, and a large piece, formed of the lateral lobes consolidated together to near their tips, on the ventral face. Deretaphrus ignavus (Pl. LVII figs. 94, 94a). Median lobe long, slender and tubular, with median orifice at tip on dorsal side, median foramen at base, which is slightly swollen. Tegmen consisting of two short, broad lateral lobes, rounded at tip and bearing a strong curved spine at base, between which the median lobe passes. Basal-piece short, projecting as two short struts (a) at base. Internal sac undifferentiated. Some other species (which cannot be determined but are not D. piceus, the type of the genus) are of the same construction with slight difference in details. Cerylon histerordes (Pl. LVII fig. 95). The aedeagus consists of a long, tubular median lobe, swollen at its apex, across which is the median orifice; and a small ring- shaped tegmen articulated at the base of the medianlobe. Internal sac complex, Obs.—There is great diversity among the few forms of Colydiidae we have examined. We might perhaps associate Hnarsus and Auloniwm, though there is much difference between them. Hnarsus is one of the connecting links of the trilobe aedeagus with the sheath-forms (Trogositidae, etc.) that we have at present placed in Cucujoidea. We have therefore in our table also given this genus a place in Byrrhoidea. Aulonium is more definitely Trogositoid. Deretaphrus is not thoroughly elucidated. There may 518 Mr. D. Sharp and Mr. F. Muir on the Comparative be an affinity with Rhizophagus. It is very different from the trilobe form. Cerylon is extremely difficult. If the ring at the base of the long tubular median lobe be really the tegmen as we have assumed, the genus might be said to be a trilobe form with tegmen greatly reduced, with concomitant great development of the median lobe in the tubular form. This in fact would then be a form of development in some respects parallel with what we find in Chrysomelidae.’ A thorough study of the forms at present associated in Colydiidae would probably lead to the dismemberment of the family, and would in addition throw a considerable light on Coleopterous taxonomy. Family CUCUJIDAE. Forms examined: Passandra fasciata Gray, Central America. Hectarthrum cylindricwum Sm., Queensland. Cucujus mniszecht Grouv., Japan. Brontopriscus pleuralis and B. sinwatus Sharp, New Zealand. Brontes luctus Pase., Queensland. Diagrypnodes wakefieldi Wat., New Zealand. Chaetosoma scaritides Westw. (?), New Zealand. Lhizo- phagus depressus Fabr., England. Figs. 96-101 Pl. LVIII relate to these forms. Passandra fasciata (Pl. LVIII figs. 96, 96a). Median lobe short and fairly broad, with the median orifice at tip, on dorsal aspect ; the basal dorsal edge is continued as a broad strut («), which suddenly narrows and continues as a long fine strut (b). The tegmen forms a ring, the dorsal side is formed by a pair of long lateral lobes, wide at their base, where they are consolidated together into a plate, and narrow for the distal three-fourths where they are free ; the ventral portion of the ring is formed by a broad plate attached to the outer basal corners of the lateral lobes. Internal sac very long and narrow, except at its base where it is complex ; the basal complex part of the sac evaginates easily and then forms a cross-shape body (fig. 96); the distal portion (c) has the opening at its apex and forms a semi-chitinous trough ; the lateral portions (d) are semi-chitinous ; two small diverticula (e) turn basally, and basad of these are two more that bear hairs. The rest of the long internal sac is narrow. At the apex of the sac there is a semi-chitinous tongue (f) through which the ejaculatory duct passes. The enlarged part of the ejaculatory duct forms a chitinous tube. It is possible that this part of the duct passes through to apex of the sac and forms a flagellum. ‘Anatomy of the Male Genital Tube in Coleoptera, 519 Hectarthrum cylindricum is on a similar plan, but the consolidated basal part of the lateral lobes is constricted off from the free portion and forms a distinct plate. From certain specimens that we have examined it appears probable that the chitinous ejaculatory duct forms a flagellum, and is capable of being thrust right through the tongue at apex, and entirely up the internal sac. This type (Passandra and Hectarthrum) differs from the rest of the Cucujidae we have examined in having a large plate on the ventral side of the ring-piece instead of the consolidated tegminal struts (#9). Cucujus mniszechi (Pl. LVITI fig. 97). Median lobe well developed, cylindrical, slightly flattened laterally ; median orifice on dorsal aspect near apex, the ventral edge continued into a small point ; dorsal basal edge continued into large median strut (ms). Tegmen forming slender ring-piece, with small cap- piece, bearing small laterallobes. Internal sac very long, with long, slender flagellum arising from the apex, at the tip of which the ejaculatory duct opens. Brontopriscus sinuatus (Pl. LVIII fig. 100). Median lobe small, tubular, with median orifice at tip, the basal part continued asa large flat strut, narrowing in middle and spatulate at the end (a). Tegmen consisting of a ring piece with dorsal cap, the cap being formed by a curved plate produced into two flattish lateral lobes; there is no line of division between the plate and the lateral lobes. Internal sac very long, with a long fine flagellum rising from the apex; about the middle the sac is swollen and its surface studded with fine, short spikes, In Brontopriscus plewralis the aedeagus is very similar, but the flagellum is longer, and there are four broad, short spines on the sac about a third from its base. Brontes lucius is very near to Brontopriscus, but the median strut is longer and more slender ; the middle of the internal sac slightly dilated and covered with long strong hairs and the rest of the sac sparsely covered with stout hairs. Diagrypnodes wakefieldi (Pl. LVIIT figs. 99, 99a). Median lobe slender, curved and membranous, with a thin chitin- rod on each side to support it; median orifice on ventral aspect near tip. The tegmen forms on dorsal aspect a large cap, which is 520 Mr. D. Sharp and Mr. F. Muir on the Comparative formed by two pieces articulated together, the distal one bearing two small lateral lobes. It is possible that the distal piece is the basal part of the lateral lobes, and the basal plate is the basal piece. The basal corners of this basal plate meet under the median lobe, No differentiated internal sac. Chaetosoma scaritides (Pl. LVIII fig. 98). Median lobe slender, chitinous on ventral aspect, membranous on dorsal ; median orifice on dorsal aspect of tip, ventral edge pointed and projecting beyond dorsal edge. Tegmen forming a ring, with large dorsal cap-piece formed of a large curved plate with a pair of broad lateral lobes at apex; the ring is broad and continued as a strut (tg) on ventral side. Internal sac small, not differentiated. There are probably more than one species of Chaetosoma in New Zealand, and if so the one here dealt with is not the C. scaritides of Westw. Ours is a comparatively large, black form, found by Commander J. J. Walker at Wellington. Rhizophagus depressus (P|. LVIII fig. 101). Median lobe large, tubular and slightly curved ; median orifice at apex, the base prolonged into a long dorsal strut. Tegmen forming a slender ring round the median lobe, the dorsal part slightly enlarged into a very small cap-piece. Internal sac large, with stout, twisted flagellum arising from apex. This differs from Nitidulidae by the large, exposed median lobe, the cap-piece of the tegmen reduced so as not to cover the lobe. This family is of great interest and requires much greater investigation than we have given it before any definite conclusions can be arrived at. It will eventually have to be divided. Whether or not certain divisions that have already been proposed are adequate we cannot say. Chaetosoma is of interest as it shows a probable transition from the sheath type (Trogositidae) to the true ring type. In Diagrypnodes we have a type nearer to Pythidae than to Cucujus. The degree of differentiation of the sac and the condition of the lateral lobes must be considered in adjusting the relationships in this family, Thus Hectarthrwm has a more generalised tegmen than Lthizo- phagus wherein its reduction to a mere ring is very Anatomy of the Male Genital Tube in Coleoptera. 521 considerable. There are several other Cucujus-forms (Prostomis, etc.) that we have not been able to examine, although they are probably taxonomically important. Family HELOTIDAE. Form examined: Helota gemmata Gorh., Japan, and a second species from Assam. Figs. 106, 106a and 1060 Pl. LX. Helota gemmata (Pl. LX figs. 106, 106@, 1060). Median lobe broad, flattened ; the ventral face forming a plate of which the lateral edges project slightly ; the base prolonged into two broad struts; median orifice at distal end. The tegmen formed of a large “cap-piece” on the dorsal aspect and a Y-piece on the ventral. The edges of the cap-piece are turned in and form a groove in which the projecting edges of the median lobe run. In- ternal sac large with complex armature at apex. This armature (fig. 106b) consists of a stout chitinous block (a), on the end of which the ejaculatory duct opens; the ventral face of this piece forms a shallowly curved plate (b), on the dorsal aspect are two curved plates, both deeply cleft at the tips (c). This type must be placed somewhere near the Niti- dulidae. It is an instance—and far from a solitary one— of an aedeagus within an aedeagus. Family OMMADIDAE. Form examined: Omma stanleyi Newm., Australia. Omma. stanleyi (P1. LIX figs. 102, 102). Median lobe well developed, tubular with median orifice on the smaller distal end and the median foramen at the larger basal end ; two short median struts; point of articulation on dorsal face. Lateral lobes large, concave on the inner surface, where this envelops the median lobe to near its tip, the basal part of the lateral lobes consolidated together. No defined basal-piece. The internal sac is simple and of medium size. In this species the anus opens at the end of a chitinous tube (a) which either represents the last segment (tergite and sternite) or a chitinisation of the rectum, more probably the former. 522 Mr. D. Sharp and Mr. F. Muir on the Comparative Family CUPEDIDAE. Form examined: Cupes clathratus Motsch., Japan. Figs. 1038, 103a, 104, 104a, 1045 Pl. LIX. Cupes clathratus (Pl. LIX figs. 108, 103a, 104, 104a, 1040). Median lobe small with median orifice on ventral aspect, forming a longitudinal opening along the distal two-thirds. Tegmen com- plex without distinct division between the basal-piece and lateral lobes. On the dorsal side there is a plate (a) bilobed at tip, which covers the median lobe. A pair of large lateral lobes with complex tips, and from near their bases, on the ventral face, two long, slender spines (b) are given off. Internal sac undifferentiated. There is a unique structure pertaining to the dorsal plate of the last visible abdominal segment (104, 104a, 104)). Asin Omma the anus opens at the end of a chitinous tube (c), from below it there rises a pair of flattened chitinous processes (d). The last visible dorsal plate is deeply cleft at its distal margin, its basal part con- tinues into the abdomen, curves under and ends in a point, a hole (e) being left just before the bend, through which the gut passes. Obs.—As regards Omma and Cupes; though very peculiar they are by no means closely allied, and form two families more naturally than a single one. It is by no means impossible that the peculiarities of these two Coleoptera are indications of an old relationship with Insects of another Order (perhaps something that preceded the existing Sialidae). We really, however, know very little about the creatures and generalisation is premature. We find that their wings even have been but imperfectly studied. Family CRYPTOPHAGIDAE. Form examined: