ARGONAUTA. 130 



onmge-colorcd :iiiiiual, finely si)rinkk'(l witli purplish dots, the 

 urins 1. 2. 4. .') ; the web extends alonii' only one-lialf of the 

 fourth ijjiir, and is proi)ortionally shorter than in A. Argo ; 

 there is also a slight difference in the arrangement of tlie lingual 

 denticles ; the shell is stated to be more ventricose with a dif- 

 ferent arrangement of sculpture and tubercles. Finally Reeve's 

 fig. 2 e. (fig. 121) is referred to — doubtfully as an illustration. 

 The Museum of the Academy possesses a specimen from Cumana, 

 precisely like the above-cited figure (which represents a shell 

 from the same' locality), and which is assuredly A. Argo. 



Mr. Dall calls his second species A. expansa.^ and cites the 

 Gulf of California as locality. He appears to have seen but a 

 single specimen, which he describes as differing from A. Pacified 

 in having ears or lateral expansions, and in sculpture. The 

 Museum of the Academy possesses a specimen collected by 

 W. M. Gabb at San Pedro. Cal. (fig. 120), which answ^ers well 

 to Mr. Pali's description, but is not separable from usual eared 

 forms of A. Argo. 



.The Indo-Paciflc A. compresui. Bl. {A. maxima., Gualt,), some- 

 times attains a considerable size. 



I figure the Mediterranean or ty[)ical A. Argo. the auriculed 

 A. compressa^ the agglutinated A. papyria and the A. Argo of 

 Reeve, fig. 2 c, which mo.y represent A. Pacifica. 



A. FRAOiLis. Parkinson. 



Shell Avith numerous milk-wdiite spots. Sinus large, furnished 

 with a callus, which is attenuated towards the edge of the lip, 

 and is carried across the base of the aperture from one sinus to 

 the opposite, in a flattened arch ; upon this arch rests one side 

 of the nucleus of the shell ; which is not involuted like other 

 species, but rises in a cylindrical form, a half-inch above the 

 a,rch from which the inner side springs. Around this cylinder 

 are a number of lines of growth ; but it is not tubercled, and 

 has the shape of the end of the finger of a glove. 



In other respects this specimen answers to the description of 

 A. Argo. I believe it to be a pathological specimen of that 

 species. Many individuals of A. Argo show the milk-white spots 

 given as one of the specific characters. 



No locality. 



