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TREPOSTOME IDENTIFICATION KEY 
In order to identify trepostome bryozoans from Clog-y-fran thin 
sections are needed. Ideally at least two oriented sections (longitudi- 
nal and tangential) are required. However, specimens can sometimes 
be identified from randomly oriented sections. Identification can be 
hindered when specimens are fragmented and abraded. The key 
aims to aid identification, but results should be carefully checked 
against the complete descriptions and the illustrations of the species. 
1. Zoaria massive and hemispherical i2 
ZR ATIANCTO CE sca cease cea cectineSces cat adie Soe teers eae ates nantes een ad ear CHU 3 
10. 
Hil. 
14. 
C. BUTTLER 
Ring diaphragms present . Hemiphragma sp 
Ring diaphragms and mesozooecia absent ................4+- Monotrypa sp 
Hemiphragms present 
Ia (S049) AVEYSTROTS GIDSTESAL | se ccacoecacoeroasonecandocctucenosceedne caso sporeccScossoaceecsadeououc 
Mesozooecia abundant with numerous diaphragms along their length 
af caves sayccqtemeeseaneataze rvarautnas dune dn dese catines meateuceeaneeees Dittopora sanclerensis 
Mesozooecia present, but not common. ...... Hemiphragma pygmaeum 
Cystiphrasms|presemtrese stot seeeee ee era cee eee eee ere ae 6 
Gystiphra smStaDSen tye snc: cvecsects ss dees asp usec seuaes wesc eee ere eee ee one 7 
Abundant acanthostyles present ............ Monticulipora aff. compacta 
Small indistinct acanthostyles present .............. Homotrypa cf. similis 
INGEVNINOS HPS [OSS cccesonecccececo scenes cooseo sno Lee so SaoeReeee LALoScEboDRO ASN SOSEOS 8 
AcanthostylestabSemtieeee: seeere seen este ee eee eee 15 
DiaphrapmsirareinlautaZOOcclabereseeeee eter eee een ene 9 
Diaphragms abundant in autoZO0ecia ..............eeceeseeeeeeeeeeeeeseesenees 12 
Mesozooecial walls constricted at the position of the diaphragms pro- 
ducingia beaded appearance see ee eee eee Hetrotrypa sp 
Mesozooecial walls straight in appearance ..............:eseeseeseeeeeeeeeees 10 
BYPAVINS ASS 333) AEN THM CHANTS cpopceccacosco ecocc cceccecercoseoscoscascoosece/nsoscets 11 
Branches <3 mm in diameter ...........:..:c:ceseeseeceeeereee Leioclema sp. B 
Acanthostyles composed of broad hyaline core with no sheathing 
TAMMAIT AC iy set cdaek pace veereseestea see hes vb eatesseuesvecateeecesmeenseeeee Leioclema? sp. 
Acanthostyles composed of broad hyaline core surrounded by steeply 
dippinpiconicalilaminde lesen eee ene Leioclema sp. A 
Autozooecial basal diaphragms very abundant and regularly spaced 
{BaTCOYUYSA NOBUO STINT cecaeconaencocosecscneenceuccnencoacoseccadeab bc30 Amplexopora sp. 
Autozooecial basal diaphragms present throughout colony but more 
abundantymngthe/exOZOme peeceeaeeeee eentee teeter see eet 13 
Meandering autozooecia roughly parallel to branch axis in endozone 
then curving very slightly to meet zoarial surface ..............::.:ssceeeeee 
aukestauccead kieee totes as teetoeeeack cua secsuagh eect omer ne ay Eridotrypa simulatrix 
Straight autozooecia roughly parallel to branch axis in endozone curve 
to;mectizoariall SUGLACE: ..2-<.cccewcscuss «hevses-au-crseeeun eee eee eee 14 
Thick exozonal walls with abundant diaphragms 
sa baeee vices acvnts doe inst eden essa aan socd eee Batostoma cf. polare 
QUST WASE as. eee. ceece nce coccesc hens c te sesegee sc sateccnee Batostoma clogyfranense 
MesoZO0€ClaNpTeSe mb ivsicseness ssessceeesbslencanesecsbessvtsesseuntataavusteeesseenteataaes 16 
Mesozooecia absent, exilazooecia present . Halloporina cf. crenulata 
Mesozooecia beaded in appearence ................... Hallopora peculiaris 
Mesozooecia straight-walled .............. Hallopora aff. wesenbergiania 
