’ es eee ror es 264 24 ne ene eke rtse : aherts reese Steers: tet Z : ; . ; / zee t.35 sate Sores ¢ t oe mt . 1 Le oh ns { iyi ‘ { * Wo Se PIS RE 2a == * + 4 F += 4 . 3 : : Mi Fens Eat ores Fe $22 ea sp Ersisttstarerteseeges: = itipennaeene 5 EE gogo bes #2 E . % ; . Faeeaee : ; 2 rts y : 2 eesie Ry besask cs sese lee; - - ; é : = bs sirtes 2 oe * é : FE remiss tae ier Se SE ate te ee ae ee oe = < y > ripe - . + ses ; tet : ; “=> : - z pest ee pstn ee ps apse Set erstsaetereis tress ; Sctecsareesls : i 23 fe? zs ; : pE35 ; ae ; : pres = Rte S- RSA SS A hone - A: : rtcese Se. Serer yones — = ee * SESE SRE CS ee SEE Leap es sts sith a at Sie tere tnt cae tgp tly > ¢ L aieaieniee sa Tae « 2 2 omens x es a Ce hs tanta Deane THE NAUTILUS A QUARTERLY JOURNAL DEVOTED TO THE INTERESTS OF CONCHOLOGISTS VOL. XXXII JULY, 1917, to APRIL, 1918 i497) EDITORS AND PUBLISHERS HENRY A. PILSBRY Curator of the Department of Mollusca, Academy of Natural Scietices PHILADELPHIA CHARLES W. JOHNSON Curator of the Boston Society of Natural History Boston Ae } \ i f a Me ‘ ; Ne uh CE y ane PRY) Waid hy has A ey is a BA 4 INDEX THE NAUTILUS, XXXII. INDEX TO TITLES, GENERA AND SPECIES. meets haldemant (Desh). Bint)... 2). 26/0 Jee ee ee se 92 Patemeere, Mew species OF es be es es cc tigi ere case © a 142 Amnicola bakeriana Pilsbry, n. sp. .................. 44, 87 Amnicola bakeriana nimia Pilsbry, n. var. ........... 45, 87 pamseour cClakwes PF itmbiry. “1 69 8 sss es 45, 88 Anmicola gneida Piisbry, Wh. sp... 3. ee 46, 88 Amnicolide from Oneida Lake, N. Y. ............... 44, 87 Parmer mariees Gr F Alii Ls (cis wee eh eo a = shel 142 LS SB PE) RE eae aie a a ee AR 35 Ampullaria globosa var. sinistrorsa ................0.4. 36 meaewuae oC (nema imke, NY. wo. ee ws 90 Ancylide, revision of the classification of North American 1 ere Cree eet Es 80.2 0 Gees ee eo sg eps cle wk 8 gen eaETT UME RUEES oon c 5 ga 2 xe oS bk lash W's e's a wa 5, 6 PURO ae MRO oa cals nine soc seen 4+ FEO TUS SIEM Oe RINE aS ce koe ale eo wll ee Oe 3 Ancy tis Hite) We mee UN ns le ee es 8 Ancylus rivularis Say (pl. 2, fig. 3) .. 2.0... cee eee 3 Tip y lis’ Walmer? Fite ees ob. cc ies cc as a teens 114 Peet Ga Wirers: oD eran: clos iain kale jn a aiea ye ne 121 Arkansia wheeleri Walk. & Ortm. ................. 112,121 Breonees: molhises Of Clare Gi)... oo... ete ee 109 mere POaeiee Crates, | cee eel... « csawterd ists a clals 10 peecereree ween neta) Pitt) Te SPD es... o. slp aid ws aa wie 11 Peemmetrees Gate WNOPER 2 Une s,s os eek died «a9 34 Boreal land and freshwater shells, notes on ............ 12 gg RS a pe) RR 140 Cmsnetnna fewien Walker .. 00001... ee ne in wee 116 Carychium exiguum floridanum, n. subsp. (pl. 8, f. 4,6). 73 ili iv THE NAUTILUS. Cepolis lacipeta Poey ... 5). 020 2e pee eee ee eee 43 Cepths ovumremnli ‘Lea |... oso ee ee, ee 42 Cerithopsis anaitis n. n. for C. helena Bartsch not Boettger 72 Chondrus Reichenbach 1828, replaces Modicella Ads. 1854 81 Circinaria vancouverensis from Unalaska.............. 13 Clark, William Bullock (obituary) ................... 68 Collecting shells in a corner of the Sierra Nevada ...... 31 Crenodonta perplicata Con. '.()3).. pape eee ene eee 122 Cuba, collecting days about the Naval Station, Guanta- namo TAY. i. Fan eee bes Lae See ee fae ee eee 41 Cumberlandia monodonta Bay... ici swere ee ues: pawns 121 Drupa foliacea Conrad (pl. 9,\4. 4 Besoin eae oka 100 Drupa morus Lam. (pt: Bo 5041) eee oa a 102 Drupa tuberculata Blainv. (pl. 9, f.10) ............... 102 Dropa vitiensis Pils. (pl.'9, 7.5), pela ete ak ee 99 Drupa walkere Pils. and Bryan, n. sp. (pl. 9, f. 4)...... 99 Elysiella Verrill. oo. 03),. ¢s:s4: Go eee ete ashes 131 Epiphragmophora ecallistoderma Pils. & Ferr., n. sp. (pl. 1, E.B) oi veh 8 Sie eee Geen Die eee rns Lee ae 33, 93 Epiphragmophora fidelis, albinistic .................. 72 Epiphragmophora tudiculata Binn., var. .............. 33 Epiphragmophora veatchii, station of ................. 144 Kurynia subrostata Say. 0: . c/o ate 118 Ferrissia (Laevapex) diaphana Hald. (pl. 2, f.4)...... 3 Ferrasia tivilaris Say (pli as ah roe vacae ee lee aes 3 Werrisennse Walker, n: Bu DERI 0.6 5s:chens be Rok es ata 2 Wisherola Tiannipal.;.. .)..s. eee ees hie ee ee he ae 2 Florida, a list of shells from the east coast of .......... 53 Friday Harbor, Washington, a summer’s collection at... 95 Fusconaia, a new type of the Nayad genus ............ 58 Fusconaia. barnesiana Thea oe) ico eos ss sale bein ted ee 59 Fusconaia ozarkenmis Call io. 6. a’... . ods ee ee 62 Fusinus sandwichensis Sowb. (pl. 9, f. 8).............. 100 Gastrocopta contracta climeana Van. ...............4+- 114 Gratacap, Louis Pope (obituary) |». dedi SN ee ae 135 Goniobasis livescens Menke «..’. ... ). tae oa aie ee bea 88 Goniobasis lawrenett Tien. .'... . .. 22 Page heen 117 Gundlachia ancyliftormis Pir... S08 fates ak ae Gundlachia hinkleyi Walker, n. sp. (pl. 1, f. 10-16, pl. 3, BE) es 5 eee eee eee PT RNP a eee py 4,51 Helix hortensis at Digby, Nova Scotia ................. 58 Helix nemoralis in Knoxville, Tenn................. 107, 133 Ischnochiton conspicuus, notes on the variation of ...... 37 Ischnochiton pilsbryanus Berry =— I. (L.) nipponica Berry as cee bee CO ee ee ee 144 THE NAUTILUS. V DES oS ASE EBS ae ta SR I 4 Kennerlyia forresteremsis, Nn. Sp. ..........-e eee eeeeees 134 i VEE AR te OE ees ys oe bk oo 3 Lampsilis minor and L. villosa, distinctive characters of. 15 Lampsilis ventricosa cohongoronta in the Potomac River. 40 ans Kiamatnensis’' Hann. (pli 2yi2) .. 0. ee een 2 Pare peeonouies Hea (pl 2. T Ly a bit a. 2 Lymnea emarginata mighelsii from Alaska ............ 12 Tyme. of Oneida hake; NOY i... se ee ne ne 92 Piacroceromus Tesius Grundl.) fio fe aii ce ee sie cc eee 43 Micromya lienosa nigerrima Lea ................0000. 118 Mollusca of Clark County, Arkansas .................. 109 Mollusca of Oneida Lake, N. Y., further notes on the... 81 Mopalia imporcata lionotus, n. subsp. ................- 126 EIST Ns ETS BREA Ds Aico TGS eh irene a (oy Seeeme am a 125 Mopalia muscosa laevior, n. subsp. .............e00000- 126 pepowaneo© money (peo T'S LA Porras mes ve 99 Naiades, new genera and species of Central American... 47 Nayades, the anatomy of two African ................. 75 OCIS A Whe BEM ea hf 1a en aeRO Aa bet 500) 47 esonure tarquhari Piabey, i ap.) 622. eae eee 50 WNesopupea ariquatandica MUR PB... ok cc ewe eee d1 meter ta tree. CTT core neces ew cons ewe 128 Pere Aarons Eanid Sel 3 seh. ke a ee eee 71 Note on the relation of snail fauna to floods ............ 64 7 OEE RNORE EERE Feat ree Glemrana Snr prednT ab 35, 71, 107, 144 Nova Scotia, collecting at Digby ................2008- 57 RE ER eh a 71 Oreohelix handi Pilsbry & Ferriss, n. sp. ............. 31, 94 Peristernia thaanumi Pilsbry & Bryan, n. sp. (pl. 9, f. i ee ETRE VE VE CE EG ae aera Pana ee 101 Physide OB CC St yo cs a ecek scene aege 89 Planorbide of Oneida Lake, RM hey dg teeme et areas raced 90 PaatOP Diy BAMINIIOI AGEN Oe Gio). 6s ss ka co sien eee 114 Plecotrema cubense from the mainland of Florida ...... 5D Peere MICA WRTHICINOR ESOP! VG 6’. nerds Semis a ee 43 Polygyra albolabris maritima in Massachusetts ......... 108 Polygyra obstricta carolinensis Lea ................... 116 Deepest Gay OPDOreadl .) oo sete. so ae ae se «o 36 Polygyra columbiana from Unalaska .................. 13 Polygyra texasiana tillandsiz Cockerell, Ni VEE as ice ee 36 Ee RCAC 6S 2, Shain o wah abeea dled es 36 Psoronaias kuxensis Frierson, n. sp. (pl. 7, f. 1,2)...... 48 Deen POCTVER 0. ko ae ce adn 's bd ee ate 34, 69, 108, 140 pNMAININEEE ARCOM 05 Ls a Sew edie eda kale ees 79 vi THE NAUTILUS. Rhodacmea cahawbensis Walker, n. sp. (pl. 1, f. 4-6).... 7 Rhedacniea elatior Anth. ss. 0 se ee 8 Rhodacmea filosa Conrad (pl. 3, f. 2) .............220. 6 Rhodacmea gwatkiniana Walk., n. sp. (pl. 1, f.3,7,9).. 9 Rhodacmea hinkleyi ‘Walk: 2. cece oaebicee sek ee 8 Rhodaemea rhodacme Walk., n. sp. (pl. 1, f. 1, 2, 8; pl. “Te Oe: } Pape Ta Cert pcky tea SA 00) a RR A Rhodacmiea Walker, di rene.) doce eae bs are D Bhodacmeine, n: subiadtt, | .Jos). i cae eee eee kha be 5 Rhodocephala ‘Walker, m1. sect. :..). jc dis eek oe as ere 9 le 8 Sampson, Francis Asbury (obituary) ................. 137 Shells collected at Anaheim Bay and vicinity .......... 103 Sigaretus, a new Californian: .. 4), ate vais a od wlohe kid ba aie 13 Sinum californicum /Oldroyad, B. 6B.) l ck sews «beh 13 Sonorella rooseveltiana Berry, n. sp. ..........002e000 14 Spatha Kamerunensis Walker .3. 0.6. ecae evened 17 Spatia walberoi Kiri oy coeab ace ee ees ace 77 Sphaeriide, notes on reproduction and growth in certain. 16 Sphaermdm of Oneida Tike Niki es vl baie te wn eb ee 84 Strobilops labyrinthica texasiana Pils. & Ferr.......... 114 Buccizies retusa: Lien fish ler eee lames a ta adie che eae 93 Thysanophora caeca Guppy (pl. 8, f.3)................ 75 Thysanophora dioscoricola C. B. Ads. (pl. 8, f. 2)....... 75 Thysanophora macneilli Clapp, n. sp. (pl. 8, f.1)....... 74 Traghydermon owe Diy sds wie koe ik ee es oe at eee 127 no ehiter Mera. os cs ee GLK dois ee ew epee 75 Unio tetrainamus Say (OL Vite Aye eae ales sateen 49 Unionidie of Oneidh Lake, ie Wie eis ihe ee otk bins eae koe 83 Unios, on the rate of growth of pond .................. 49 Vallonia cyclophorella septuagentaria Pils. & Ferr., n. VAT en ONE Ay Aik 2 EE RE 3 (6 kp eat 95 Valvata tricarinata perconfusa Walker, n. n. .......... 36 Valvatide of Oneida Dake Way... ....: > ds0chees Gee 89 Vitrea radiatula circumstriata Taylor ................ 115 Vivarium, a home-made :.). 3)... . . .s'dseus ehwecee eee 105 Viviparids of Oneida Take, N. Y.. . 2.0) .8 553.45 e0eeuee 86 Viviparus malleatus and contectoides in Mass. ......... 107 Walkerola. Hanna ai) .6).. 2/0 «'-;nieeal et ep ete ee 2 Winkley, Rev. Henry W. (obituary) 00.0 cc se scenes 136 Zachrysia emargina. Pir. (pl. 7,28 Taide sab ot be + os 79 Zachrysia ramsdeni Pils., n. sp. (pl. 7, f. 5,6) .......... 78 THE NAUTILUS. vil INDEX TO AUTHORS. PMR OR ERM Ron Sse Came rah ak es ota dad lcwe oaaw.s 81 INTER ts. 0!) x OTT) No Sia ha ada Waal we ie nl epg oo 144 I Oe oe ars at ae 107 nr ia) iS PN ee anh aretha wich at ane's 71 MES 9 0a aig ce! ns Ab Re abana a etatas tasers baie dce wb e/e acetad « 14, 144 em TR BR) Re Lara tbs ha dda) din oh be a, dm wae 99 Bg 2) gata ad a Bea A Marc rate scakmiet eke la ayo. a Saal @ 37, 103 Rm EB CV Sa Gel aren bath aie ot ie alia yg 73 UE Ye PHPBB ae ec da 36, 108, 133 UMS AR = SUNOS DE Ue Bete rs oo So 8 ee Se RET 9 10, 12, 34, 93 cog NE IRL S Aes ed eT Paes Bees CAD 31 MMMM SITES Oe Sg Lincs na aiica Carnie 4 apart bar ined a wo 6 47, 49 Meme TRMMLENIB CANIN Oo cal ia. alge cedlxvaver a dim! aya aa eeY I Costa w 16 mes RIMMER og ahaa ins Saag fa Ge a btu ca taal ans 137 epuerenre: Oboe Ps ek li Na Ss as 41 RR NS We AO Ee Si i ke 107, 136, 140 0 OTE NE LOCUS A DVRS gag ETL PD RUE See OE RES oe A 72 MERIAL ANS MG ea ae lh pa el A 40 nD RE ROR RE Us gc chat a uid aiwianetaha dinte er ocd sim bo 13 MS SCCM Ne pe tte aS ok a ak hal wig atl kl ig a calate 95 een Mem. oC LAA eeu, 58, 75, 78, 93, 99, 128 NIE GPEC OC Rw Pees ra EM a A hi 44, 50, 125 Oe AE SEITE HE SSO 8 Canta 1 PEERS NP ae ee ee 64 gE ECD |) ea eee 2 Ee Ce ee 57, 105 Pr aMIaRt OR ee Pee ee es. ide ol 71 Ty aR RAN Me tia eee Wie ah alain w dieldie = 48 15 WE AIMGr. Ton vanie ase ss oe srl as sais 1, 35, 51, 53 er Peeler) (EUs cian No. e aeerenens hae es MOUNTS thw ola Bale 109 eer es | Spee Sir Penman ose ba nla oc a Galera 134 Renee): Peau Grav, 7d, SR Rena el!) te 131 ¥ bl My (phy FRE Ny } ‘hy AeA (2) Balt f % hi) a 4 . f ; ay 4 : é ! Uj ‘ = iv ie | ; etee Ps sib uu i ‘ ef s a) eu Vale ': ewe ls y (it ¥ i Bey ; “ Hl . VA, ; é ; Ue eae es i d nf © A 4 | es ’ Mw « + «& Ri — . . ? ' ss q ‘ * x , : é i LA, ; ‘ Cy ee de ee "Ag! i> , : 5 ~ a ’» ed a le t 6 Ge ea ack TRG Aero) nn A. BN ne ral ( " ; ‘ TURE OU En Ulan) bit bil Pie 7a eA A HRS. A eC fs bd ‘ ; én Bie’ vy eve t NYRR ye Dou 2 ln i , ae q 7 yh a \ ¢ tik ’ “kA i ia: a4 @ f OC Ober aah h aoe Lo * | ‘ < Vit «ff 4 ely Career bal , » " OU ge ee BY CALE ne ae bate ‘ “4 any 4%) She ety id cit A { r é 1 4 : 7 i R } { a vy rh ‘ ve Fi eiarwa 4A ray dal Se 8 Pe ae oe oe Ce a ’ ‘ thy ry Wye i . ee me at ei we ee re eau ne ia ary Pa P ay) iy iis ; on ' uh f ih lie ’ : Toad iar ARUN auvaY By aK, A D f uPA Me AL Ad hae i- oper i pe wd 0 i« 4 a ¢ eu uF j he ud) id ¥? 4 : ' } f r NW Aidan #4 vt “ e) i vita wih £9) BAe! & PR Le AAD A ‘ eae # Ke . c ‘. rin’ rt it ‘ *s BY, ) “4 biG ie i A> |e *¢ ‘ A eo. J , rd we v. DEP ; gy A ; fy Ue ey ae ¥ ae pe ie Wha Wid hati aaa ME She GT ‘OPA os, f i , a i: ' t iy TATA SAMBA ah giee TRNeEES ft 4; J vie 5 ‘ ; ‘ars Cy fa ke AT Af area te re ee Oe ais ‘ a ; ¥] : iat Sih! a 5 -T he t i ae ed " | eA: as a tae VE 5 ‘ =r a eae wt ‘ iW 7 Ae ee ee tae hoe i? ' i) 0.9). 3 ii) 7 PR, oe BY, \ Nf ; YA ar. 1 > Ay | rot : ; ie Y eee obsess , ‘eve Antu? 4 sh) 1} e AWE 8 THE NAUTILUS. VoL. XXXI. JULY, 1917. No. i A REVISION OF THE CLASSIFICATION OF THE NORTH AMERICAN PATELLIFORM ANCYLIDAE, WITH DESCRIPTIONS OF NEW SPECIES. BY BRYANT WALKER. The North American patelliform species of Ancylidae can be conveniently and naturally arranged in eight genera and sub- genera according to their shell characters. These can again be grouped into three subfamilies characterized by the peculiarities of the radula and jaw. It was hoped that a study of the soft anatomy might reveal other peculiarities co-ordinating with those of the radulae, and for that purpose with the kind assistance of correspondents in England, South Africa and this country a very considerable amount of alcoholic material, representing nearly all of the characteristic groups, was collected, some of which will be very difficult to replace. This material was placed in the hands of a distinguished zoologist, who undertook to work it up. After appropriating and using the material thus obtained, it was a matter of bitter disappointment, after having waited for three years for the completion of the work, reported from time to time to be in progress, to be informed by the gentleman that he should not proceed further with the work as he did not think that it would ‘‘ pay for the trouble considering the more impor- tant anatomical details that await study among other families of mollusks.’’ Under these circumstances the subfamilies represented in our 2 THE NAUTILUS. fauna must for the present be based wholly upon the peculi- arities of the radula and jaw. The arrangement of the Ancylidae proposed by Hannibal, (Pr. Mal. Soc. Lond., vol. x, 1912, p. 147), is not based upon any distinctions of systematic value. The genera and subgenera arranged under the different subfamilies are entirely heterogen- eous and in several instances genera and their subgenera appear in different subfamilies. The whole arrangement is absolutely futile and must be entirely disregarded. The arrangement that I would propose is as follows:— I. Subfamily Lancinz, Hannibal. Jaw as in Lymnaea with two accessory plates. Radula also Lymnaeid in character. Central tooth unicuspid or tricuspid, laterals bicuspid with large quadrate bases, marginals comb- like, the cusps extending beyond the base. This group was proposed, but without any definition, by Hannibal (Naut., vol. xxviii, 1914, p. 24). Genus LANx Clessin. Lanx Clessin, Con. Cab., Ancylinen, 1880, p. 10. Type, Ancylus newberryt Lea. Example, Lana patelloides. (ieeee) SPL, ies at, Subgenus Walkerola Hannibal. Walkerola Hannibal, Pr. Mal. Soc. Lond., X, 1912, p. 149. Type, Lana ( Walkerola) klamathensis Hannibal, Pl. 2, fig. 2. Conchologically Walkerola appears to bear the same relation to. Lanz that Levapex does to Ferrissia. | Genus FisHEROLA Hannibal. Fisherola Hannibal, Pr. Mal. Soc. Lond., X, 1912, p. 151. Type, Fisherola lancides Hannibal. Nothing has been published on the soft anatomy. It is. placed here on account of its size, shape and habitat. Il. Subfamily Ferrissin#, n. subf. Jaw segmented in plates. Radula with a bicuspid central, laterals obliquely reflected with from two to five small cusps. THE NAUTILUS. 3 arranged somewhat like the teeth of a comb, marginals also comb-like, cusps not (usually) extending to the basal line. Genus Ferrissta Walker. Ferrissia Walker, Naut., XVII, 1903, p. 15. Type, Ancylus rivularis Say. PI. 2, fig. 3. Subgenus Levapex Walker. Levapex Walker, Naut., XVII, 19038, p. 16. Type, Ancylus fuscus C. B. Adams. Example, Ferrissia (Levapex) diaphana (Hald.). Pl. 2, fig. 4. For reasons stated elsewhere (Naur., XXVI, p. 117), I can not follow Hannibal in subordinating Ferrissia to Levapex. I agree fully with Gwatkin (J. of Con., XIV, 1914, p. 147), that Ferrissia represents the most primitive type of radula, so far as yet known, in the Ancylide. The world-wide distribution of the genus is evidence tending in the same direction. Levapex is restricted to America and is, to my mind, clearly an offshoot from the more ancient Ferrissia stock. In addition to its pecu- liar shell characters, there is some evidence tending to show a slight divergence also in the character of the lateral teeth, but hardly sufficient to justify its generic distinction. Genus GUNDLACHIA Pfeiffer. Gundlachia Pfeiffer, Zeitschr. fur Malak., VI, 1849, p. 98. Type, Gundlachia ancyliformis Pfr. Pl. 8, fig. 1. Poeyia Bet., (1862), and Kincaidella Hann., (1912), are synonyms, being based on immature or non-septate stages, but the latter name may be retained for the group with striate apices. Gundlachia, like Ferrissia, includes two groups characterized by the presence or absence of radial sculpture on the apex. I have examined all of the described species except G. cre- pidulina Guppy from Trinidad and G. lucasi Suter from New Zealand. Sub-genus Gundlachia s. s. Apex smooth, except for light concentric wrinkles. Type, Gundlachia ancyliformis Pfir., Cuba. The following species also belong in this group: 4 THE NAUTILUS. G. bakeri Pils., Brazil; Ainkleyi Walker, Guatemala and Ajal- marsoni Pfr., Honduras and Texas. Sub-genus Kincaidella Hannibal. Apex radially striate. Kincaidella Hannibal, Pr. Mal. Soc., London, XII, 1912, p- 148. Type, Ancylus fragilis Tryon—Gundlachia californica Row. Californica Rowell, (March, 1863), has priority over fragilis Try., (June, 1863), if the date given by Binney, (L. and F. W. Sh., II, p. 149), is correct. Kincaidella also includes the following species: G. beddomei Pett. (MSS.), and petterdi John. from Tasmania; neozelanica Suter from New Zealand; l’hotelleriei ‘‘ Bgt.’? Walker from Egypt; a species as yet undescribed from Cape Colony, S. Africa; californica Rowell, meekiana Stimpson, stimpsoniana 8. Smith and undetermined species from Starved Rock, Ill. and Mobile, Ala., from the United States. The generic position of Ancylus woodsi John. from Tasmania would seem to be somewhat uncertain, (see Hedley, Navrt., IX, p. 66), but, if not a Kincaidella, it is a Ferrissia, as the apex is radially striate. It is interesting to notice that Gundlachia s. s. is apparently restricted to the countries bordering the Gulf of Mexico and seems to be a purely American group, similar to Lerapez, while Kincaidella, like Ferrissia s. s., has a range extending quite around the globe. Ifa natural rather than an artificial system of nomenclature could be used, Kincaidella would represent the older and really typical group and Gundlachia s. s., as a more recent off-shoot from the original race, would become a sub- genus. I have not seen Troschel’s description of the radula of G. ancyliformis mentioned by Hedley, (Naut., IX, p. 62). The tadule of the three American species that have been figured, californica, meekiana and hinkleyi, are all very similar to each other and quite different from that of either Ferrissia or Leva- pez. That of G. neozelanica Suter as figured in T. N. Z., XXVI, pl. 14, fig. 5 is similar in the small number of cusps on the THE NAUTILUS. 5 side teeth, but differs in having them longer and sharper, those of the marginals extending beyond the base. This characteristic difference in the raduJa would seem to definitely establish the generic validity of the group. III. Subfamily RoopAcMEINz#, n. subf. Jaw composed of numerous segmented plates. Radula with a long, slender central, unicuspid or faintly bicuspid, and with the base widely expanded in some species: the first lateral very large with an enormous mesocone, the blade-like cusp extend- ing beyond the base, the ectocone is back of the mesocone, en- tirely separated from it and has several small cusps; there is no endocone. The four laterals are similar in shape but diminish rapidly in size toward the margin, these are succeeded by two or three transition teeth, smaller and with more or less imper- fect cusps. The marginals are very small, rapidly decreasing in size toward the outer edge, with large quadrate bases, wider than high, vestigial, the cusps being nearly, if not quite, obsolete. | The rows of teeth are more or less V-shaped and with the immense laterals and minute marginals present a remarkable appearence quite unlike any other group belonging to the family. Gwatkin, (J. of Con., XIV, 1914, p. 147), has already com- mented upon the resemblance of the radula to that of Brachypo- della. All of the species known to belong to this group have the apex of the shell tinged with pink. Genus RHODACMEA, N. g. Shell patelliform, conical, elevated or depressed, apex tinged with pink. Radulaand jawasinthesubfamily. Soft anatomy otherwise unknown. Type, Ancylus filosus Conrad. Pl. 3, fig. 2. The species belonging to this genus are not confined to the Coosa drainage as Gwatkin supposed, but are also found in both the Tennessee and Ohio systems. As in Lanz and Ferrissia, two well marked groups are repre- 6 THE NAUTILUS. sented in this genus, the one with an elevated and the other with a depressed shell. Section Rhodacmea, s. s. Shell elevated. Radula with a unicuspid central, which has the base triangularly expanded; laterals with the cusp of the mesocone extending but little beyond the base and not over- lapping the base of the central tooth. Type, Ancylus filosus Conrad. I. RHopaAcMEA FILosa (Conrad). Ancylus filosa Conrad, F. W. Shells, 1834, p. 57. When I wrote of this species in 1904, (Naut., XVIII, p. 75) I had not seen any specimens from the Black Warrior River, Conrad’s original locality. The specimens then before me as was stated, were not typical in that they lacked the ‘‘ numerous, radiating, prominent lines’’ described by Conrad. Since that time a considerable amount of additional material has been received from Mr. H. H. Smith, which fully confirms the origi- nal diagnosis. One set from the Black Rock Shoals of the Black Warrior River are rather thin, of a light translucent green color with the apex tinged with rose and are very strongly radi- ately striate, the ribs extending from the apex to the periphery. The largest specimen measures 4.25 x 3x2 mm. These shells are undoubtedly typical. Similar specimens are before me from the Coosa River from several localities, viz., two miles above Coosa Valley, St. Clair Co.; Ten Island Shoal near Lock no. 2; Leota Shoal; Three Island Shoal, Wilsonville, Shelby Co.; and Vincent Shoal, two miles above Upper Clear Creek. Also from Tallassahatchee Creek, four miles east of Childersburg; Beaver Creek at Greens- port and Canoe Creek. All the shells from these localities are quite typical in form, but are uniformly thicker and more heavily striated than the Black Warrior specimens. This heavily striated form seems to be the characteristic expression of the species in the Coosa and its tributaries. The Cahawba River specimens from Lewis and Call mentioned in my former paper, while lacking the strong THE NAUTILUS. 4 radial striae, are in texture and shape like the typical shells from the Black Warrior. While this smoother form quite probably represents a local race worthy of recognition, as it has not been found by more recent collectors and no exact localities for it are known, it hardly seems advisable to do more than to call attention to its peculiarities until more definite information as to its precise range can be had. RHODACMEA CAHAWBENSIS, n. sp. Pl. I, figs. 4-6. Ancylus filosus Walker, Naur., XVIII, 1904, p. 76, pl. vi, figs. 1-6. Shell elevated, obtusely conical, broad oval, somewhat wider behind the apex than before it; apex obtuse, siightly behind the longitudinal centre of the shell, scarcely, if at all, turned toward the right side, apical sculpture entirely eroded in all specimens seen; yellow horn color slightly tinged with green, apex rose color; anterior slope convex toward the apex, straighter below; posterior slope nearly rectilinear; lateral slopes slightly convex, the left being more oblique than the right; lines of growth strong and irregular, slightly rippled by radial lines, which sometimes become obsolete radial strie. Length 4.5; width 3.5; alt. 2.5 mm. Types, (no. 43453 Coll. Walker), from the Cahawba River, Gurnee, Shelby Co., Ala., collected by H. H. Smith. Cotypes in the collections of the Acad. of Nat. Science, Philadelphia, George H. Clapp and John B. Henderson. Also from Cahatchee Creek and Yellowleaf Creek, Shelby Co., Ala. The single specimen from the latter locality shows subobsolete radial stria- tion very much like the ‘‘ Coosa River’’ specimens in the Lewis collection which in my former paper I referred to filosa, but which I now think belong to this species. The fact that the heavily striated filosa is quite characteristic of the Coosa, where this species has not been found by Mr. Smith in his extensive collections, makes me doubt whether the Lewis shells really did come from the Coosa itself. Unfortunately no exact locality is given by Lewis and the question must remain undetermined. This species is more closely related to the elatior Anth. of the Tennessee drainage than to any of the known species of the 8 THE NAUTILUS. Alabama system. Compared with that, it is smaller, narrower, with a more obtuse apex, the posterior slope is straight and not convex and the lateral slopes less oblique than in that species. The tinted apical area seems smaller than in the other species of the genus and is frequently lost entirely from erosion. The radula has not yet been examined. RHODACMEA ELATIOR (Anthony). Ancylus elatior Anthony, Ann. N. Y. Lyc., VI, 1855, p. 158, pl. v, fig. 20. No additional information in regard to this species can be given at this time except that the radula of a specimen from the Tennessee River at Florence, Ala., collected by Hinkley agrees with that of jfilosa in the characters of the central and lateral teeth. A very considerable collection from the Tennes- see made by Mr. H. H. Smith has not yet been worked over and may add materially to our knowledge of the species when critically examined. RHODACMEA HINKLEYI (Walker). Ancylus (Ferrissia) hinkleyi Walker, Naut., XXI, 1908, p. 139, pl. lx, figs. 11-18. The species listed from the Tennessee River at Florence, Ala., as ‘‘ Ancylus rhodaceus Walker’’ by Hinkley in 1906, (Nauvt. XX, p. 40), but not described, is the same as that subsequently described under this name in 1908. The radula of the Tennes- see River specimens agrees with those of filosa and elatior in sectional characters. Section Rhodocephala, n. sect. Shell depressed. Radula with a faintly bicuspid central which has the sides of the base straight and not expanded; laterals with the cusp of the mesocone extending far beyond the base and overlapping the base of the central tooth. Type Rhodacmea rhodacme Walker. RHODACMEA RHODACME, n. sp. PI. I, figs. 1, Z and 8. Shell depressed, conical, obovate, the greatest width being THE NAUTILUS. 9 just behind the apex, apex subcentral, only slightly behind the centre, obliquely elevated, acute, spine-like, somewhat turned toward the right side, finely radially striate, apical depression small, oval and situated on the left side of the tip of the apex; pale green with the apical region deeply tinged with rose color; anterior slope very slightly convex; posterior slope oblique and nearly rectilinear below the base of the apex; lateral slopes slightly convex and about equally oblique; growth lines regular, fine and distinct, the apical striae extend down over the upper part of the shell giving a shagreened appearance to the surface as they intersect the growth lines, but become mere ripples toward the margin. Length 5.25, width 4, alt. 1.25 mm. Types, (No. 20371 Coll. Walker), from the Coosa River at Williamsville, Shelby Co., Ala., collected by A. A. Hinkley. Cotypes in the collection of Mr. Hinkley. Also from the Coosa River above Wetumpka (Hinkley) and at Leota Shoals; Fort William Shoals; Shoal two miles above Coosa Valley; Vincent Shoal two miles above Upper Clear Creek and Peckerwood Shoais (H. H. Smith). All of the Smith shells were found on or under stones. which is apparently the usual habitat of the species, differing in this respect from filosa, which is almost invariably found on living Pleuroceride. I have adopted for this species the very appropriate name suggested by Dr. Pilsbry soon after its discovery. The peculiar depressed shell of rhodacme with its spine-like apex and characteristic radula differentiate it very sharply from the species included under Rhodacmea s. s. and justifies the establishment of a special section for it and similar species. RHODACMEA GWATKINIANA, n. sp. Pl. I, figs. 3, 7 and 9. Shell rather small, depressed conic, oval; apex nearly cen- tral, somewhat turned to the right, acute and _spine-like, finely radially striate; apple-green with the apex tinted with old-rose color; anterior slope slightly convex; posterior slope oblique and nearly straight below the projecting apex; lateral slopes straight below the base of the apex and equally oblique; growth 10 THE NAUTILUS. lines rather coarse and irregular, the entire surface covered with low, coarse, rather distant radial striae extending to the edges. Length 3.5, width 2.5, alt. 1 mm. Types, (No. 43454 Coll. Walker), from Butting Ram Shoals, Coosa Co., Ala., collected by H. H. Smith. Cotypes in the collections of T. H. Aldrich, George H. Clapp and John B. Henderson. All of the specimens were found on living Pleuroceridz. This beautiful little species, which groups with rhodacme in. its depressed shape and spine-like apex as well as in its radular characteristics, differs from it in its small size, more regularly oval shape and the greater development of radial strize over the- surface. It is named in remembrance of the late Rev. Prof. H. M. Gwatkin of Cambridge, England, to whom I am indebted for practically all of the radula preparations used in this paper and who was the first to observe and point out the remarkable char- acter of the radula in the different species of the genus. I am indebted to Dr. Pilsbry for the slide representing the radula of Lanz patelloides. All of the other radule figured were prepared by Prof. Gwatkin, and all of the figures were drawn by Mrs. Lydia M. H. Green formerly connected with the. U. S. National Museum. A NEW SPECIES OF ASTARTE FROM ALASKA. BY WILLIAM HEALEY DALL. In 1865 Dr. Philip Carpenter described from a single speci- men a species of Astarte from Puget Sound, to which he gave the specific name of compacta. This type remains in the collec- tion of the National Museum as number 4509. This species has remained extremely rare, only three or four others, some eroded and doubtful, have come to hand during the half-century which has passed. This is probably due to. the fact that the right locality had not been dredged, for the- THE NAUTILUS. 11 species of this genus are usually very abundant in their chosen places. Recently Mr. G. Willett, warden of the Forrester Island res- ervation in southern Alaska, has succeeded in getting an excel- lent shell-collection at this isolated spot; among the shells thus obtained was a good series of Astarte compacta. With this, and for a time confused with the latter, is what seems to be a new species of Astarte, which Mr. Willett in arranging his collection was the first to discriminate. He had the kindness to send me his fine mounted series of both species for examination, the re- sult of which is not only that a new species is identified, but it is shown that A. compacta as well as the new form belong to the typical section of the genus, both forming at intervals cren- ulation of the inner margin of the valves. The only specimens of A. compacta previously available happened to be in the stage without crenulations. The new form is best described by a comparative diagnosis. ASTARTE WILLETTI, n. sp. Shell small, of a yellowish-brown externally, milk-white in- ternally ; the external sculpture of small concentric waves is more regular and constant than in compacta; the form is more oval and the beaks more anterior than in that species, and wil- letti appears to attain a larger size. In compacta the lunule is relatively narrower and longer than in the new species. In the interior the hinge of the latter is better developed than in com- pacta, all three teeth being usually represented, while in com- pacta the posterior and particularly the anterior cardinal is fre- quently obsolete or absent. The shell substance of A. compacta is more translucent and bluish, and the crenulations of the valve margin when present are distinctly smaller and less conspicu- ous than in willetti. The measurements of two forms are as follows, the largest specimen of a series of some twenty-five specimens being selected in each case. Height. Length. Diameter. A. willetti 14 16 8 mm. A. compacta 12 12 6 mm. 12 THE NAUTILUS. The specimens were dredged in about 50 fathoms. The um- bones in A. willetti are 6.0 mm. behind the anterior end of the shell; in A. compacta about 5.5 mm., the result being that the latter has a more triangular outline. The type of A. willetti is number 216364 of the catalogue of mollusks of the U. S. Na- tional Museum. NOTES ON BOREAL LAND AND FRESHWATER SHELLS. BY WM. H. DALL. The National Museum has received a small lot of fresh-water shells from Dr. T. E. Winecoff, stationed at Fort Yukon, Alaska, nearly on the Arctic circle, which are of more than ordinary interest. They were collected from a small pond near the fort and the large Lymnaea abounded in such numbers as to give a pinkish tint to the water in which they were, accord- ing to the collector. The species are: TIymnaea appressa Say, rather small for the species, and of a brownish tint not unlike the usual color of L. palustris. Lymnaea palustris Miller. Ordinary type and size. Lymnaea emarginata mighelsti Binney. Not known so far northwest. Planorbis trivolvis Say, medium size, abundant. Planorbis crista Linné, onespecimen. Nearest known locality is Carberry, Manitoba. Pisidium vesiculare Sterki, one specimen. During a cruise in Bering Sea last summer, Mr. G. Dallas Hanna touched at St. Mathew Island in the northern part of Bering Sea. From small ponds in the island he obtained the following species: Aplexa hypnorum Linné. Planorbis parvus Say. Valvata mergella Westerlund. Pisidium scutellatum? Sterki. Succinea chrysis Westerlund. THE NAUTILUS. 13 Several times during the last few years I have received the two forest snails Polygyra columbiana and Circinaria vancouver- ensis from Unalashka. At first I felt confident that some error had occured in labeling, as during my visits at that locality, 1871 to 1880, there was no grove or forest to shelter them and assiduous collecting failed to reveal their presence. However, in 1899 I found the transplanted Sitka spruce planted on one or two of the islets in the bay had made an extraordinary growth, and as these snails are always associated with the spruce and fresh specimens have been lately received from the locality, I can no longer doubt that the introduction of the species and its acclimation have been successful. The Circinaria are small and of a dark olive-green, the Polygyra normal. A NEW CALIFORNIAN SIGARETUS. BY MRS. IDA 8S. OLDROYD. SINUM CALIFORNICUM, N. sp. Shell white, convex, spirally striate above, with epidermis of a rusty yellow; a thin columellar callus reflected nearly over the umbilicus showing only a faint trace of umbilicus; interior snow-white. This has been called Sigaretus debilis Gld., but it is not like the specimens from Lower California. It differs from S. concavum in not being as convex, and the interior being white, and the early whorls are much smaller, and from S. debile in being convex and larger. SS. debile is very flat, the early whorls are smaller and fewer. Length of shell 38 mm., breadth 18 mm., height 18 mm. The type comes from San Pedro, California. The type and nine specimens are in the Oldroyd collection at Stanford Uni- versity. Others are in the collection of the U.S. Nat. Museum, from localities ranging from Monterey, Cal., to Todos Santos Bay, Lower Cal. 14 THE NAUTILUS. A NEW SONORELLA FROM ARIZONA. BY S. S. BERRY. Mr. George Willett has sent in specimens of a Sonorella from Gila County, Arizona, which do not seem referable to any of the described species. A diagnosis is accordingly offered below. SONORELLA ROOSEVELTIANA new species. The shell is depressed. In the type the spire is low conoidal, but in some specimens is higher, while in others is raised but little above the level of the principal whorl ; umbilicate, the umbilicus contained about eight times in the major diameter ; very thin and fragile. Whorls 44 to 44. Embryonic whorls a little less then 14, the initial half-whorl very finely, irregularly, radially, wrinkled-costulate, the wrinkles becoming finer and more wavy in the following whorl, where they are crossed by a series of fine, delicate, raised lines, passing obliquely down- ward and forward from the summit of the whorl to the suture, the sculpturing sometimes showing with beautiful regularity over most of the whorl. Yet when aseries of shells is examined the finer sculpturing shows great variation. Frequently the incised lines are more or less interrupted, especially near the summit, into elongate papillae which later coalesce. Some- times lines or papillae are evident running in a direction counter to those just described and intersecting them. Above the sum- mit, where the wrinkly lines of growth come closer together, the appearance is more granular and less distinct, but occasional traces of similar lines apparently pass obliquely downward (actually wpward on account of the depression of the whorl at the suture) and backward from the superior suture to the sum- mit. In most of the specimens the fine wrinkling becomes al- most granulose. The next whorl-and-three-quarters show irre- gular growth-lines crossed obliquely by lines of minute papillae, though I can make out no bristles with the aid of such magni- fying power as happens to be by me. The last whorl is appar- ently smooth except for the lines of growth. This whorl is moderately wide and descends slightly in front. The aperture THE NAUTILUS. 15 is subcircular and very oblique. The peristome is thin, its margin only slightly thickened and scarcely at all expanded or reflexed except at the base. There is an excessively delicate parietal callus. The type measures, alt. 8, major diam. 16.5, lesser diam. 14 mm. ; diam. of umbilicus 2 mm. ; aperture 8 x 8 mm. Largest specimen, alt. 11, major diam. 19 mm. Smallest adult, alt. 7, major diam. 15 mm. Type: Cat. No. 3733 of the writer’s collection. A paratype is Cat. No. 117086 of the Academy of Natural Sciences of Phil- adelphia, and another is in the collection of George Willett. Type Locality : Roosevelt, Gila County, Arizona; in rock slides on north slopes, 2200 ft. altitude. 31 specimens exam- ined, taken by Mr. George Willett, December 15, 1914, and November 1916. Remarks: Although the shell characters of this modest species offer no very striking peculiarities, I have been unable to iden- tify it with any of the sixty or so described members of the genus. There is apparently no end to the Arizonan Sonorellas. As compared with the other species of which I have seen speci- mens, S. rooseveltiana seems more than usually thin and fragile. The general porportions of the shell, as the spire, aperture, and so on, are quite variable. Some of Mr. Willett’s shells have found their way into other collections as S. coloradoensis Stearns, from the figures a quite different species. Redlands, California. THE DISTINCTIVE CHARACTERS OF LAMPSILIS MINOR AND L. VILLOSA. BY T. VAN HYNING. In sending out specimens of the Unionidae of Florida from the Florida State Museum, we have stated of Lampsilis villosa B. H. Wright, and Lampsilis minor Lea, that it was impossible to differentiate with certainty all of the adult specimens; this 16 THE NAUTILUS. being due to the eroded umbones, but with young specimens showing umbonal sculpture, it was an easy matter. Simpson says in his Descriptive Catalogue for both species, that the um- bonal sculpture was not seen; hence no description. This museum has numerous specimens of young and adult of both species recently collected, and the young show the umbonal sculpture of both species to be composed of about four coarse ridges; in minor they are circular and in villosa V-shaped looped. Mr. Frierson, in a letter of November 27, '16, writes that he has discovered how to differentiate the adults of these two species. He calls attention to an additional small muscle scar (cicatricula?) at the upper end of the anterior muscle scar (cicatrix) in minor. I have just found time to go over the specimens in this museum and open them up, and separate them according to Mr. Frierson’s discovery, and I am now prepared to give some additional information. In the majority of specimens a glass is required to see the small scar referred to, and then in the majority of specimens the small scar, instead of being separate, is but an extension of the larger one, which makes it still harder to determine. Simpson says, of minor, ‘‘ anterior scars deep,’’? and of villosa ‘‘ muscle scars scarcely impressed.’’ In opening a shell, the deep scar in minor is at once noticeable from the shallow one of villosa. Minor is a heavier, wider, and shorter shell than villosa, and the anterior distance from the umbo is shorter in mznor. Florida State Museum. NOTES ON REPRODUCTION AND GROWTH IN CERTAIN VIVIPAROUS MUSSELS OF THE FAMILY SPHAERIIDAE. BY RALPH J. GILMORE. The present study was undertaken in an effort to determine the nature of the reproductive process in certain common forms of the family Sphaeriidae. For a long time incubation of the young has been known to occur in European forms, but no in- vestigation has been made of related forms from America. THE NAUTILUS. 17 HistortcaL. Jacobsen (1828) noted the fact that embryos of Cyclas develop in sacs. He observes that ‘‘each ovary is composed of a number of small cylindrical sacs or capsules. When impregnated, these sacs increase in bulk and gradually protrude from the abdomen. By this protrusion they are intro- duced into the gill cavity but still retain connection with the interior membrane of the ovary. These capsules contain the eggs and the young are developed in them. Each one contains but one egg or young one. As soon as the young has reached a certain size, the capsule bursts and the young is ejected into the gill cavity. We find in the gill cavity at one and the same time, capsules and young both large and small.’’ Apparently the only part of Jacobsen’s observations which is correct, is the fact that the young develop in sacs. Later authors fail to con- firm his work. Oskar Schmidt (1854) investigated the anatomy of Cyclas calyculata. Franz Leidig (1855) studied the anatomy of Cyclas cornea. Stepanoff (1865) was the first to point out the brood pouch of Cyclas in its true relation. His observations were confirmed in 1885 by Ziegler. However, the work of both of these men was directed mainly toward segmentation and development of the embryo and their observations on the brood pouch were mere casual notes. Im one of his plates Ziegler shows a diagrammatic figure including a small portion of a brood pouch. De Bruyne (1898) in a work on phagocytosis figures a brood pouch. Poyarkoff (1910) published a prelim- inary note on the incubation of embryos of Cyclas. This was followed in 1911 by a paper on the same form by Schereschewsky. Both of these authors gave considerable attention to the cellular structure of the pouch, its origin and function. The only work that has been published on American forms is that of Drew, who in 1894 described the anatomy of Sphaerium sulcatum. MatTERIAL. The material for this work was collected during the summer and fall of 1913, from ponds and streams in the neighborhood of Ithaca, N. Y. Two forms were observed, Calyculina truncata and Sphaerium simile. Calyculina truncata is one of the smallest of the Sphaeriidae. It averages about eight millimeters long, and seven high. The shell is very fragile, rhombic ovate, the posterior part very 18 THE NAUTILUS. squarely cut off, the anterior broadly rounded. The surface is smooth and shining with very fine lines of growth. The color is light yellowish green or greenish horn. It occurs in clear fresh-water ponds or the sheltered parts of rivers, usually em- bedded in soft sticky mud, the siphons protruding just above the surface. Very often it may be seen climbing about on sub- merged vegetation. Theseasons of greatest apparent abundance are the spring and early summer months. It quite frequently occurs in ponds which are dry throughout the greater part of the year. Sphaerium simile is one of the largest species of the family. An adult specimen may be eighteen millimeters long and thir- teen millimeters high. The shell is rather solid, almost equila- teral, transversely oval (Fig. 10), the anterior and posterior margins almost equal. The surface is shining, pale green, with coarse growth-lines in young specimens but in older ones it is. dull, dark brown to black with only those growth-lines evident which mark the ends of growth periods. It prefers clear, cold streams but may be found in quiet pools of rivers and lakes. It buries itself in soft mud or debris usually an inch or more below the surface. It communicates with the water above through a small hole in the mud. I have no record of this form occurring in places which are not well supplied with water throughout the year. MetHops. During the early part of the work, expanded animals were fixed in hot water or hot mercuric chloride. This method had one great advantage, in that it allowed very litte contraction of organs. But for cell structure the following was found to be better. The animals were prevented from completely closing the shell by a small piece of wood inserted between the valves. In this condition they were placed in cold saturated mercuric chloride with two to three percent of glacial acetic acid. They were kept in the fixer for twenty-four hours. The acidity of the fixer removed nearly all of the calcium salts of the shell. The remainder was removed by one half to one percent of hydrochloric acid in sixty-seven percent alcohol. The entire animal was imbedded in paraffin. Serial sections were cut from six to ten microns in thickness. Delafield’s Pili es! “ad, | ee ak SP a J we a) At PLATE I THE NAUTILUS, XXxXI WALKER: ANCYLIDA THE NAUTILUS, XXXT PLATE IE 1. LANX PATELLOIDES (LEA). 2. LANX KLAMATHENSIS HAN. STAREATR APP POP PP PD ay ee it Mee |! i 3. FERRISSIA RIVULARIS (SAY). 2B ARAL ESHA NN 4. FERRISSIA (LAN APEX) DIAFHANUS (HALD.). THE NAUTILUS, XXX! PLATE IT ues Bd STD VS WN WI SBR PRA aoe bead i 1. GUNDLACHIA HINKLEYI WALKER. 2. RHODACMEA FILOSA (CON.). 3. RRODACMEA RHODACME WALKER. PLATE IV THE NAUTILUS, XXxXI GILMORE: REPRODUCTION OF SPHARIIDE THE NAUTILUS, XXXI PLATE V NE Oy ' = : Oy = =< = 2 ff 4 \ E ff \ \h fe I {| \ i D an VLE I ) hi A hii HF =\h a) B HY a —\t 4} Boe fe “Wh | ww |- ew, OG ENG. = ' \ | cn lad ) ect Ww iar | tp thy it Vy Yul GILMORE: REPRODUCTION OF SPHAERIIDA PLATE VI THE NAUTILUS, XXXI L1G. 10. Fie 11 GILMORE: REPRODUCTION OF SPHERIIDA 7 ee /~ om 2 ne P ied . wer vi 6d > is ’ 4 + ro bal ‘ ae ft te ~ mer als . ws ? * , THE NAUTILUS. 19 Haematoxylin and orange G. in ninety-five percent alcohol were used as stains. In order to establish the relation of the brood pouch to the gill filaments and water spaces a wax model of parts of a gill was constructed from drawings made on an Edinger machine. REPRODUCTIVE ORGANS. The animal is hermaphroditic. The reproductive organs are situated beneath the pericardium and behind the stomach (Figs 1, 2, 3,4). They consist of a pair of racemose glands, the anterior part of which produce sperm and the posterior eggs. A common genital duct continues backward, opening into the cloacal chamber of the inner gill near the opening of the kidney. PlateWV, Fig. 2, represents the essential parts of an egg fol- licle. Each follicle is lined with a single layered epithelium supported by a very heavy basement membrane. Eggs develop by the enlargement of certain cells of the lining epithelium. When a developing egg has grown to four or five times the size of the neighboring cells it is pushed out of its position by a pedestal-like growth of the basement membrane. Thus pro- jected into the lumen of the follicle, it continues to develop until mature, when it drops off. The sperm-producing follicles (Fig. 3) are irregularly spher- ‘ical and arranged about their common duct like the parts of a raspberry. ach follicle is made up of a mass of sperm mother cells about its outer part and either fully formed or young sperm cells near the center. The center is hollow and com- municates with the common sperm duct. This duct (Pl. V, Fig. § extends a short distance backward where it receives the product of the egg follicle, continuing from that point to the exterior as a common genital duct. Regarding maturation and fertilization Stepanoff (1865) ob- serves, ‘‘ When the egg has reached a certain size it separates more and more from the wall of the basement tissue until it at last becomes free, in the inner part of the follicle and later falls into the outlet of the sex glands. The separation is affected by the increase of the yolk mass and the resulting weight of the egg. Eggs thus fallen into the duct become surrounded by a mass of fully formed sperm, so that, without doubt, fertilization 20 THE NAUTILUS. occurs in this place.’’ Schereschewsky says, ‘‘ Fertilizatiom takes place in the gill chamber.’? In the majority of the speci- mens of Calyculina and Sphaerium ripe sperm and eggs were found to occur in the same individual. None of the specimens. had eggs in the genital duct. BREEDING Seasons. The breeding season probably continues through the greater part of the year. Observations on this point have been very meager. Animals taken in November and December of 1913 were found to contain, in newly formed brood pouches, eggs some of which were unsegmented and others in very early cleavage stages. Considerably over fifty adult speci- mens have been sectioned. All were found to contain young in several stages of development. Gitts. Before considering the structure of the brood pouch it will be necessary to look into the structure of the gills. The gills are four in number, an outer and aninner pair. The outer is much smaller than the inner and falls short anteriorly by about a fourth of its length. Each gill has two lamellae. The outer lamella of the outer gill is attached to the mantle; the inner lamella of the outer gill is attached to the outer lamella of the inner gill and the inner lamella of the inner gill is at- tached to the body. It is the outer lamella of the inner gill which contains the brood pouches. The lamellae are made up of gill filaments (Figs. 7, 8, and 11). A typical filament may be compared to a rubber tube sharply bent on itself to form a letter Y. Each filament of one lamella is therefore continuous with one of the other lamellae. The open part of the letter Y represents the cloacal chamber. All water which passes between the filaments finds its way into this chamber and from thence to the exterior. In the anterior and posterior parts of the gill the cloacal chamber is very much reduced (Figs. 8 and 11). Each filament is a hollow tube which in frontal section ap- pears as an irregular ellipse (Figs. 8 and 11). The outer part is made up of a single layer of heavy cells, strengthened by > chitinous rods (Fig. 8). The inner part is a single layer of flattened cells forming a very thin membrane. The hollow THE NAUTILUS. 21 part of a filament is the blood space. This blood space may be crossed by an irregular loose network of web-like threads. ‘These probably serve to prevent the membrane from collapsing. In the ventral part of the gill, except at the ventralmost part, the blood spaces of the two lamellae are kept separate as is shown (Figs. 5, 7 and 11). At irregular intervals adjacent filaments are joined by inter- filamentary junctions (Figs. 7, 8 and 11). Small ribbon-like bands of fibrous chitin may join several filaments for a short space. These by holding the filaments together give definite shape to the lamellae which would otherwise be a tangle of tubes. Another type of junction (Fig. 8) is made by the direct fusion of the elements of two adjacent filaments. This is the more common form of junction in the dorsal part of the gill. At the most dorsal part the filaments lose their identity entirely nd fuse to form large blood spaces. Between the filaments are water spaces which communicate with the mantle chamber on the outside and the cloacal cham- ber on the inside. Water is kept flowing from the mantle cham- ber to the cloacal chamber and the excurrent siphon by cilia. The outer surface of the filaments is covered with short cilia, the sides have a narrow row of longer ones. CIRCULATION OF THE Bioop. The most important function of the gills is the purification of the blood. Blood leaves the ventricle by two main arterial trunks, the one supplying the anterior and the other the posterior part of the body. These vessels end in blood spaces which have no definite wall. The ‘spaces of the greater part of the body pour their blood into the inner lamella of the inner gill (Fig. 5). Passing first ventrally in this lamella, it turns at the bottom of the gill and comes up- ward through the outer lamella. In the dorsal part of this jamella the filaments fuse to form a large sinus which becomes the auricle and empties into the ventricle. The outer gill de- rives its supply of blood from the mantle and such parts of the body as are near by. Blood enters the outer lamella, crosses to the inner lamella and enters the heart by the same channel that carries blood from the inner gill. It should be noted that the brood pouches are admirably located. For they are bathed B29 THE NAUTILUS. by blood which has just left the alimentary tract and later received its supply of oxygen. Broop Poucu. Fig. 8 represents a fully formed brood pouch as seen in frontal section. The pouch has two distinct walls, an outer and an inner. These are direct continuations of the heavier portions of adjacent gill filaments. The outer wall con- sists of a thin one-celled membrane made of flat expanded cells. This wall is, in every respect, similar to the membranous part of the gill filaments. The inner wall is also made up of a single layer of cells. A part of this wall is similar to the outer wall though the major portion is composed of very thick glandular cells. Between the outer and the inner walls is a blood space. This space is a modification of the spaces of the two filaments to which the two walls are attached (Fig. 11). Numerous web- like cross threads occur in the blood space. These are similar to those which are found in the spaces of typical filaments. They furnish another proof that the two walls are mere modifi- cations of filaments. The brood pouch may contain but one embryo (as in Fig. 8) or it may enclose a number (as in Fig. 11). A pouch may involve two filaments and only two (as in Fig. 8) or it may be constructed from the parts of several. The inner wall of such a pouch is thrown into folds which di- vide it into communicating chambers. These folds probably represent the contributions of the several filaments. Just how the pouch originates is still an open question. Stepanoff (1865) and Schereschewsky (1915) believe it to be a modification of gill filaments. In Calyculina and Sphaerium all the available evidence points to such an origin. The wax model shows the pouch to be a modification of ordinary fila- ments. The same filaments enter into the structure of the pouch throughout its extent. Poyarkofi (1910) offers this theory for the origin of the pouch: ‘‘ When the embryo comes into contact with the gill filaments, it is surrounded and enclosed by leucocytes. Later these ar- range themselves in two layers forming the brood pouch.’’ He considers ‘‘the incubation of embryos in Cyclas as a case of ectoparasitism accompanied by the formation of a follicle at least in part, perhaps altogether mesodermal.’’ Schereschewsky THE NAUTILUS. 23 ‘reviews Poyarkofi’s work and can find no good evidence to substantiate it. One fact may be significant to show that the glandular inner wall is not astructure which must be derived from other sources than filaments. In the dorsal part of the gills all of the fila- ments are fused to form a heavy-walled blood sinus. This wall is made up of cells which, in every respect, resemble those of the inner wall of the brood pouch. NUTRITION OF THE EmBrRyo. Schereschewsky observes that the embryo in the brood pouch is bathed by a distinct fluid which contains many acidophile granules. This fluid is the secretion of the large gland cells of the inner wall of the pouch. Poyarkoff has a different theory. He says, ‘‘there are large cells of the inner wall of the brood pouch which serve for the nutrition of the embryo. At a certain time they become de- tached and fall into the lumen of the pouch. Their cytoplasm becomes homogeneous and eosinophile.- Their nuclei take a uniform stain. The chromatin granules become almost com- pletely indistinct. The embryo swallows these large cells. I have found these large shells in the intestine of some embryos. Stepanoff (1865) and Ziegler (1885) have noted this mode of nutrition.’’ Poyarkoff further observes that the cells which have thus fallen into the cavity are replaced by leucocytes. Figure 9 is a copy of one of his illustrations. Schereschewsky has reviewed these observations and can find no evidence to justify them. In Calyculina and Sphaerium I have found un- doubted evidence of secretion in the brood pouch. I have found a few cells thrown out into the lumen of the pouch but have considered this a normal phenomenon to be expected among actively secreting cells. As to the cells supposed to have been eaten by the embryo, may these not have been parasites ? Sexual Maturity. Gross examination of the gills of Sphae- rium revealed young so large that it was thought probable that these young might themselves be bearing embryos. Examina- ‘tion of microscopic sections proved that such a condition does not exist. The smallest specimen found to contain young was ten millimeters long. This is two millimeters longer than the 24 THE NAUTILUS. largest young one found within the brood pouch. Several nine-millimeter specimens were sectioned’ but none were found to contain young. Young six, seven, and eight millimeters long have sex organs fully formed. I have no sections of very small Calyculina. The young of this form within the parent’s. gills are in the same stages of development as to the sex organs, as those of Sphaerium. In the table which follows are included the results of gross examination of a number of Sphaeria. This is incomplete, since it was not possible to determine the presence of any young under five tenths of a millimeter. The animals examined were taken during July, 1913. Size Total Total Percentage Length inmm. Examined Bearing young Bearing Young 7 5) 0 0 8 12 0 0 9 27 0 0 10 21 0 0 11 30 0 0 12 45 0 0 13 30 2 6.6 14 40 10 25 15 47 22 46.8 16 64 51 80 17 64 53 83 18 14 14 100 19 + a 100 SPHAERIUM BEARING YouNG OVER .5 MM. Lone. Ges Number bearing Total of Per cent of young class class 13 2 30 6.6 14 10 40 25. 15 22 Wir ds. 46.8 16 51 64 80. 17 53 64 83. 18 14 14 100. 19 4 a 100. THE NAUTILUS. Gd Size oF YOUNG TAKEN FROM ABOVE SPHAERIUM BY GROSS DISSECTION. Size Frequency Per cent of whole oO 1 .04 1. 16 6. 1.5 6 2. 2. o7 14, 2.5 9 3. 3. 26 10. 3.5 3) 1. 4, 28 10. 5. 37 14, 6. 4] 15. 7. 55 20. 8. 8 3. 267 young irom 400 adults taken haphazard. | The size of the young was found to be independent of the size of the parent. An eight-millimeter young is as likely to be in a fourteen-millimeter parent as in one of eighteen milli- meters length. The majority of the above contained two young, one in each inner gill.