SM THE TERRESTRIAL MOLLUSCA INHABITING 



Pease, who described examples from the latter group, does not mention the color, 

 which varies from whitish-corneous to luteous or dark brownish-horn color. 



It belongs to a peculiar group, which Prof. Mousson has named Trochonanina. 

 They differ from the typical Microcystis in being acutely angulate, and conical or 

 trochiform in shape. Like the latter, they have the columella either simple or 

 toothed. 



The animal is pale yellowish-white. The foot elongate, compressed, grooved 

 on the sides, and in length equals one and a half times the larger diameter of the 

 shell. The eye tentacles are long and slender; the labials small The mucous 

 gland is prominent. 



The mucus of this, and all the other species of Trochonanina with which I am 

 acquainted, is unusually tenacious, and the animals possess the habit of "thread- 

 spinning" to perfection ; so much so that it requires no small amount of patience 

 while gathering specimens to detach them from the fingers, and secure them in 

 the collecting box or vial. 



They are all viviparous. 



M. Samoensis, Mousson. 



Nanina Samoensis, Mouss., Jour, de Conch., 1865, p. 165. 



Helix Samoensis, Pfeiffer, Mon. Hel., v. p. TO; vii. p. 82. 



Zonites (Conulus') Samoensis, Mouss., Jour, de Conch., 1869, p. 331 ; 1810, p. 116; 18Y1, p. 10. 



Helicopsis Samoensis, Pease, Proc. Zool. Soc, 1811, p. 415. 



Zonites Samoensis, Schmeltz, Cat. Mus. Godeff., v. p. 90; Paetel, Cat. Conch., p. 86. 



This small species is very abundant beneath dead wood and under loose stones 

 in the low-land forests near the sea-shore. It only occurred to my notice at Raro- 

 tonga and Nukuhiva (Marquesas) in Southeastern Polynesia. In Southwestern 

 Polynesia it is generally diffused throughout Samoa, Tonga, and the Viti Islands. 

 Dr. Graffe discovered it in the low coral islands of the EUice Group. It never 

 occurs in the inland forests. 



It will be observed by the above references that this little shell, which was 

 described, first as a Nanina, was subsequently removed by the author to the genus 

 or subgenus Conulus. It appears to me to be more nearly related to Microcystis 

 than the latter genus, and connects the former with Trochonanina. 



GENUS PATULA, Held. 



Contrary to the views of the late Mr. Pease, I follow Prof. Mousson in refer- 

 ring the following species to the above genus. The former author classed them 

 with Pitys, and by other writers they have been referred to Endodonta. 



