\I\V MALLOPHAGA. 123 



entirely across, with narrow marginal black bands, and 

 two quadrangular smoky brown blotches separated from 

 each other and from lateral band by uncolored spaces. 



In an immature specimen (plate viii, fig. 2) of about 

 same size as adults, the markings are less intensely col- 

 ored, the occipital signature and precoxal lines of ventral 

 surface showing through, and the segmental parts of the 

 marginal abdominal bands distinct, so that each segment 

 appears to have four blotches, the outer ones darker. 



Lipeurus diversus n. sp. (Plate viii, figs. 3 and 4.) 



Several specimens taken from the Black-vented Shear- 

 water, Puffinus optsthomelas { Bay of Monterey, Califor- 

 nia). The species is very like, in outline and markings, 

 Piaget's species angusticefs (Les Pediculines, p. 306, pi. 

 xxv, fig. 4) from a Thalassidroma leachi (Zool. Garden 

 of Rotterdam), but shows such marked difference in size 

 and certain details that it must be looked on as a distinct 

 species. 



The measurements of the specimens are (following in 

 parentheses are the corresponding dimensions of august i- 

 ceps as given by Piaget) : Male, body, length 3.4 mm. 

 (2.8 mm.), width .37 mm. (.30 mm.); head, length .7 

 mm. (.6 mm.), width .37 mm. (.28 mm.). Female, 

 body, length 4.1 mm. (3.65 mm.), width .5 mm. (.46 

 mm.); head, length .72 mm. (.65 mm.), width .43 mm. 

 (.37 mm.). The description of the species in general is 

 that given for angusticefs differing as follows: Male, the 

 posterior border of the signature angularly concave, not 

 straight; the temporal margins with two short hairs in- 

 stead of one; the antennal colored bands bending inwards 

 at the clypeal suture and continuous with the internal 

 bands which bound the oral fossa; the meta thorax with 

 five long hairs on posterior angles instead of two; the 



