Vol. 5, p. 341-348. January 31, 1931. 



Occasional Papers 



OF THE 



Boston Society of Natural History. 



NEW LAND ISOPODS FROM NEW ENGLAND. 

 (on isopoda oniscqida, second paper.) 

 BY CHARLES H. BLAKE. 



In the course of my collecting trips in New England I have 

 taken two members of the family Trichoniscidae which appear 

 to be undescribed. One belongs to the typical subgenus of 

 Trichoniscus, the other to KesselyaVs recently proposed genus 

 Miktoniscus. 



The record of Trichoniscus demivirgo from Mount Desert 

 Island and Figure 1, g-h are published with the kind permission 

 of Mr. William Procter, Director of the Biological Survey of the 

 Mount Desert Region, to whom my best thanks are due. 



Trichoniscus (Trichoniscus) demivirgo, sp. nov. 

 Fig. 1, dr-h. 



Description of female. — The ground color is salmon. This is overlain by a 

 heavy, dark brown reticulation. The general form of the body is about as in 

 T. caelebs (= yusillus G. O. Sars). The surface of the head, terga, and uro- 

 pods is densely scaly. The head and dorsum are sparsely beset with short 

 setae. Tubercles are wanting. Length, 3.2-4.0 mm. 



The eyes are conspicuous and triocellate. The antennal lobe is nearly 

 semicircular, slightly angulated ventro-laterally, and ends abruptly ventrally 

 to the middle of the eye. The anterior margin of the lobe bears three small 

 spines, rather distant from one another. Seen from above, the medio-anterior 

 margin of the lobe is slightly excavate. 



The telson has the posterior margin slightly excavate and provided with a 

 pair of fine spines just mediad to the corners. Adventitious additional spines 

 may occur still more medially. 



The mouthparts are as in other members of the subgenus. The thoracic 

 logs and the uropods show nothing noteworthy, except that the uropods are 

 strongly divergent. 



The pleopods are especially distinguished by the strong development of the 

 lateral scaly areas on the bases of the first two pairs and the exopod of the 

 second pair. The endopod of the third pair is about as wide as long and has a 



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