26 Journal of Entomology and Zoology 



first appendages are short, strong and chelate, the other two ap- 

 pendages are more slender and may be moderate in length or very 

 long. All appendages or only one or two may be provided with 

 long spines near the base. Two types of protonymphon stages may 

 be recognized, the most common such as found in species of the 

 genera, Nymphou, Ammotlica, Tduystyhim, Zetes (Eurycyde) , by 

 Dohrn, Hoek, Morgan, Meisenheimer, Meinert and others. 



The genus Pycnogouiini is in a way an intermediate type for the 

 first appendage bears a long hair-like process, as shown by Hoek, 

 '81, and Meinert, '98. 



The genera PlioxichiJidiinn and Auoplodactyhis have long ten- 

 dril-like extensions from the two body appendages. These larvae 

 were first noticeci by Gegenhauer in 1854, among hydroicis, later 

 by Allman '59, in a similar situation. Both of these investigators 

 supposed that the eggs of PhoxichUid'uim were laid in the hydroids. 

 Hodge in 1862 showed that it was the larva which made its way 

 into the cavity of the hydroici polyp. Semper 1874, gives a very 

 good outline of the life history of P. mutilatum. Adlerz in 1888 

 gives more detail in the larval stages of P. femoratum. A large 

 number of others have described parasitic habits of pycnogonids 

 besides those already mentioned. Hallez in 1905 speaks of the 

 mutual modifications of larva? anci hydroid, various degrees of para- 

 sitism were found in different species. In one case the larvae were 

 from .1 mm. to .8 mm. in length in ciifferent stages, the last stage 

 being somewhat elongate in form. Mertens in '06 found a larva 

 in Tethys which he describeci as a new species of Nymphou. Loman 

 '08 was one of the latest to consider this kind of parasitism among 

 pycnogonids. Some earlier writers who also considered this sub- 

 ject were Kroyer '42, Lendenfeld '83, and Strethill '63. 



Among the Laguna Beach pycnogonids the eggs were held by the 

 males in from two to sixteen bunches. Palcuc has about two eggs 

 in two clusters. Hdlnsoma had from six to eight small bunches. 

 T. intermedium had usually about four. T. orbicular c from two to 

 four clusters. L. margiuatiis, usuallv four. A. spiuosissima about 

 1 1 bunches. A . calif oruicus sixteen small bunches of many eggs. 

 A. erectus sixteen. The eggs differ greatly in size in the different 

 species. The eggs of Halosoma are the smallest yet recorded. 



