REVISION OF THE FISH FAMILY LIPARIDAE 49 



Pyloric coeca. — The number of pyloric coeca varies from about 10 

 to 90. There is considerable variation in the number of coeca in some 

 of the species. The variation in L. callyodon is from 42 to 64 and in 

 L. agassizii from about 60 to 90. The evidence at hand indicates that 

 when the average number of coeca is 40 or 50 the amount of variation 

 will be 10 or more and possibly as high as 30. In spite of this varia- 

 tion, the number of coeca constitutes an important specific character. 

 When more thoroughly investigated it ^vill doubtless be found that 

 the average number of coeca can be used to considerable advantage 

 in designatmg species. 



The length of the coeca varies considerably, but this character has 

 not been sufficiently studied by the writer to warrant any conclusions 

 as to its value. 



In this genus the coeca are always on the right side and more easily 

 examined through an incision on this side. 



PricMes. — In 1904 Jordan and Synder proposed a new genus, 

 Trismegistus, based on the presence of "thumb-tack" prickles. This 

 is good evidence that these structures had escaped serious considera- 

 tion previous to this time. They had been noted and figured, however 

 by Liitken (1886) and Garman (1892). Jordan and Evermann, 

 1898 (p. 2107) describe the color of L. atlanticus as, "with small 

 scattered light or bluish dots over the body." These dots are the 

 bases of the prickles which they failed to notice. The writer has 

 described their presence in a number of the genera. The species of 

 Liparis upon which the writer has noticed prickles are L. atlanticus, 

 mucosus, micraspidopliorus , hristolense, ochotensis, ingens, megacepTialus, 

 rhodosoma, tandkae, and owstoni. Liitken records them in L. major. 



The significance of these prickles is unknown. In some species, as 

 L. atlanticus, the pricldes appear to be found only on the male and 

 during the breeding season. They are not solely a male character, 

 however, for the writer has examined them from the bodies of female 

 specimens of L. megacepTialus, hristolense, and ocTiotensis. Schmidt, 

 1904 (p. 191), records what he considers to be a specimen of L. owstoni 

 (probably tanalcae) as a female and "covered with thumb-tacklike 

 plates which make it rough." All the 12 specimens of L. hristolense 

 have thumb-tack pricldes. Some species, such as L. callyodon, 

 never have prickles. It is possible that in some species prickles are 

 always present on both sexes, in others occasionally present on both 

 sexes, m others occasionally, seasonally, or always present on the 

 male. Other possibilities suggest themselves but the above-mentioned 

 cover the field of probability. 



The prickles are usually or always absent from the lower surfaces of 

 the body. They may be confined to a limited area, such as the nape, 

 or distributed over the upper and latral surfaces of the head and body 



