108 



As could be expected, the distribution of this character closely matches that of character 

 #40, which deals with the approach of the palatine to the lacrimal region. Here, the lutrines 

 plus the pinnipeds are united by the derived condition, in which the jugal does not approach 

 the lacrimal. Together, both of these characters, which reflect the unusual contribution of 

 the maxilla to the anterior orbital wall, not only support pinniped monophyly [as in Wyss 

 (1987) and Wyss & Flynn (1993)], but also a lutrine affinity for the pinnipeds. The 

 transition sequence mentioned above was not consistently borne out, although the jugal 

 of Monachus spp. was observed to approach the lacrimal to a greater degree than in other 

 phocids. 



*55) dorsal process of squamosal process of zygomatic arch: 0 = absent: 1 = present (King 

 1983; Wozencraft 1989). 



With recoding, this character was included in character #56. 



56) degree of interlock between jugal and dorsal process of squamosal process of 

 zygomatic arch: 0 = weak; 1 = medium; 2 = strong; 9 = dorsal process of squamosal 

 absent (Wozencraft 1989). 



This character stems from the oft-cited observation that the squamosal process of the 

 zygomatic arch and the bifurcated distal end of the jugal form an unusual interlocking or 

 mortised contact in phocids (Mi vail: 1885; King 1983; Wyss 1987; Wozencraft 1989) and 

 the fossil pinniped genera Allodesmus, Desmatophoca, and Pinnarctidion (Mitchell 1975; 

 Repenning 1975; Wyss 1987; Berta 1991). However, as a similar junction, but of slightly 

 different morphology is also found in sirenians and desmostylians (Barnes 1989), we 

 adopted Wozencraft's (1989) formulation of the character, which focuses on one particular 

 aspect of the junction. The distinct dorsal process of the squamosal process he mentions 

 is found only in phocids (Wozencraft 1989) and most species of Allodesmus [see photos 

 and drawings in Mitchell (1975) and Barnes ( 1979)]. 



While we affirmed that the presence of the dorsal process is uniquely shared by all phocids 

 among the taxa examined here (see character #55), we also noted that the "'strength" of 

 the resulting interlock varies. In some phocids, the jugal merely abuts the dorsal process 

 of the squamosal process (state 0 - weak interlock), while in others, the jugal wraps up 

 and around the dorsal process to varying degrees, thereby increasing the strength of the 

 mortised contact (states 1 and 2). A medium strength interlock is the common morphology 

 for the phocids and characterizes the family primitively. The remaining apomorphic states 

 arise independently on a number of occasions: a weak interlock in Halichoerus, Lobodon, 

 and Pusa sibirica, and a strong interlock in Cystophora, Monachus tropicalis, and Pusa 

 c aspic a. 



Palate and ventral side of snout ( 1 8 characters) 

 Although the palatal region appears to contain a good deal of phylogenetic information, 

 a significant use of palatal characters is primarily limited to Chapskii (1955a) and Ridgway 

 ( 1972). A primary source of characters is the contours of the hard palate. Chapskii (1955a) 

 indicates this to be a useful source, although the high incidence of intraspecific polymor- 

 phism does tend to hinder easy descriptions for some species. 



*57) incisive foramina (= palatine fissures / foramina): 0 = absent: 1 = present (pers. obs.). 



