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DESCRIPTIONS OF SEVEN NEW SPECIES OF ACHATINA FROM 

 THE CONGO FREE STATE. 



By S. I. Da Costa. 



Read Wth January, 1907. 



PLATE XX. 



The writer is indebted to Mr. George Grey for his kindness in sending 

 him several interesting shells from the southern part of the Congo 

 State, about 10° 30' IS. lat., between the watershed of the Lualaba 

 and Lufira rivers. Among them are the following seven species of 

 Achatina. Although they differ materially in form and texture from 

 one another, their general characteristics are somewhat similar, the 

 writer therefore retrains from making comparisons between them 

 and the species of other authors. His most cordial thanks are due 

 to Mr. E. A. Smith for the valuable assistance aiforded him in the 

 investigations rendered necessary before undertaking the descriptions 

 of these new species. 



Achatina Greyi, n.sp. PI. XX, Fig. 1. 

 Testa fusiformi-ovata, subventricosa, imperforata, tenuis, straminea, 

 strigis fulguratis latis fuscis, in anfractu ultimo ad basim productis 

 omata ; anfractus 7^, parum convexi, longitudinaliter striati, priores 

 minutissime granulati, ultimus fortiter reticulatus, f longitudinis 

 sequans ; sutura subcrenulato-marginata ; apex obtusus ; columella 

 leviter torta, oblique truncata ; apertura ovalis, intus lactea ; peristoma 

 simplex, acutum. Long. 58, diam. 32 mm. ; apertura 32 mm. longa, 

 15 lata. 



Achatina ovata, n.sp. PI. XX, Fig. 2. 

 Testa ovata, ventricosa, imperforata, tenuissima, fulva, strigis pallide 

 brunneis fulguratis ornata ; anfractus 7, longitudinaliter rugoso-striati, 

 priores minutissime granulati, ultimus f longitudinis sequans, striis 

 infra medium evanidis ; apex obtusus ; sutura siibcrenulata ; columella 

 recta, alba, leviter torta, abrupte truncata ; apertura oblongo-ovalis, 

 intus cseruleo-lactea ; peristoma simplex, acutum. Long. 56, diam. 

 32 mm. ; apertura 30 mm. longa, 16 lata. 



Achatina teansparens, n.sp. PI. XX, Fig. 3. 

 Testa oblongo-ovata, imperforata, tenuissima, nitida, diaphana ; 

 anfractus 7, longitudinaliter subplicato - striati, priores sub lente 

 minutissime granulati, fuscescentes, strigis castaneo-brunneis undatim 

 fulguratis picti ; ultimus f longitudinis sequans ; apex obtusus ; sutura 

 impressa ; columella recta, abrupte truncata ; apertura parum obliqua, 

 semiovalis, intus margaritacea, peristoma simplex, acutum. Long. 51, 

 diam. 23 mm. ; apertura 26 mm. longa, 12 lata. 



