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[Vol. 95 
most plesiotypic lineages. It also was suggested that: 1) Hydrovatini 
and Methlini were sister taxa, 2) Bidessini, Oreodytes, and Hygrotus 
Stephens were relatively more plesiotypic than Hydroporus, Dero- 
nectes s.L, Vatellini, and Graptodytes Seidlitz, and 3) L. lugubris and 
L. copelatoides were related more closely to Canthyporus than to 
Laccornis. 
Since that information was published, several studies have 
increased significantly our understanding of plesiotypic groups. 
First, information provided herein more definitely supports mon- 
ophyly of Hydrovatus and Methlini. Second, Roughley and Wolfe 
(1987) definitively demonstrated generic status of L. copelatoides 
and L. lugubris and assigned those species to a new genus, Laccor- 
nellus; evidence supporting a close relationship between Laccornel- 
lus and Canthyporus was reviewed. Third, Wolfe and Roughley (in 
press) completely revised Laccornis and described a new tribe, Lac- 
cornini, for the genus. 
In light of this new information, the phylogeny of plesiotypic 
hydroporines proposed by Wolfe (1985) is re-evaluated below. The 
analysis herein is facilitated by phylogenetic computer programs 
(PAUP) not previously available to me. I have found that use of 
these programs supplements interpretation of hypotheses by: 1) 
more accurately and repeatedly revealing the number of equally 
parsimonious trees derivable from a character matrix, 2) permitting 
rapid calculation of consensus trees so that similarities between 
equally parsimonious trees can be ascertained, 3) more definitively 
allowing assessment of assumptions used in tree construction ( e.g . 
character weighting, character ordering, and addition and elimina- 
tion of taxa), and 4) allowing easier comparison of trees in terms of 
homoplasy and tree length. 
In summary, it must be stressed that computer generated phyto- 
genies are not intrinsically better than mentally computed trees. 
However, I think that singular reliance on mental computations can 
be biased too easily by preconceived notions/ hypotheses concerning 
one or two trees that investigators often have in mind before in 
depth analyses even begin. Compared to purely mentally con- 
structed hypotheses, computerized constructions (and associated 
kinds of output) reveal in a more definable and consistent way the 
frailties of a given hypothesis(es). Although various assumptions/ 
limitations that are explicitly exposed through computer analysis 
