THE ANNALS 



MAGAZINE OF NATURAL HISTORY. 



[EIGIiTFI SERIES.] 



" perlitora spargite museum, 



Naiades, et cireiim vitreos conaidite fontes : 

 PoUice virgineo teneros hie carpite flores : 

 Floribus et pictum. divse, replete canistrura. 

 At V09, o Nymphse Craterides, ite sub undas ; 

 Ite, recurvato variata corallia trunco 

 Vellite museosis e rupibus, et mihi conchas 

 Ferte, Deae pelagi, et pingui conchylia suceo." 



N.Piirfhenii. Gianneffasi, Eel. 1. 



No. 13. JANUARY 1909. 



I. — A Case of AJmormal Oviducts in Homavus vulgaris. 

 By W. G. RiDEWOOD, D.Sc, Lecturer on Biology nt 

 St. Mary's Hospital Medical School, London. 



The lobster which forms the subject of the present note was 

 ^iven rae by Dr. W. T. Caiman, carcinologist at the British 

 Museum, whom I have to thank not only for the specimen, 

 but also for information respecting the literature of abnormal 

 genitalia in the higher Crustacea generally. The specimen 

 was sent to the Museum from Billingsgate Fish Market, and 

 was stated to have been caught off the Orkney Isles. 



On the right side of the body the normal oviducal aperture 

 is present on the base of the third or antepenultimate leg 

 (fig. 1, a), but on the left side there is no aperture on the 

 third leg ; instead there is an opening on the basal joint of 

 the fifth or last leg (where the vas deferens of the male 

 normally opens), and another aperture on the fourth leg 

 (fig. l,c&h). ^ 



Abnormalities in the generative system of the lobster 

 {Homarus vulgaris^ are apparently very rare, altliough in 

 the Norway lobster or Dublin prawn [Nephrops norvegicus^ 

 and in freshwater crayfishes they occur with comparative 

 frequenc}'. 



Ana. (j& Mag. N. Hist. Ser. 8. Vol iii. 1 



