Zodiac and Late Roman Army Organisation

[Flavivs Aetivs]

Pseudo-Hyginus
you set the limit of the camp-order regarding Hyginus to Marcus Aurelius` reign (round about 170/180AD) - which is ok for me.

161-180.

[...]Haec erat grauis armatura, quia habebant cassides catafractas ocreas scuta gladios maiores, quos spathas uocant, et alios minores, quos semispathia nominant, plumbatas quinas positas in scutis, quas primo impetu iaciunt, item bina missibilia, unum maius ferro triangulo unciarum nouem, hastili pedem quinque semis, quod pilum uocabant, nunc spiculum dicitur, ad cuius ictum exercebantur praecipue milites, quod arte et uirtute directum et scutatos pedites et loricatos equites saepe transuerberat, aliud minus ferro unciarum quinque, hastili pedum trium semis, quod tunc uericulum, nunc uerutum dicitur.[...]
He describes the weapons of the old Legion and say that they were equipped with Spatha and Semi-Spatha. Furthermore they had 5 plumbata (darts) attached in the concavity of the shield. They had likewise 2 spears. A longer one called Pilum - now called Spiculum. The other smaller Spear was called vericulum - now called verutum.
The next texts describes the usage of manubalistae and arcubalistae.
Not an evidence per se - however another indication, since most weapons are matching our discussed periode.

By Semi-Spatha I assume he is referring to the Gladius.

This (what you said) checks out, even though I've only taken 1 unit of Latin so far. My question is why he mentions the Spiculum? Because I thought it had fallen out of use in the late 3rd Century.
Also the term "Verutum" had been in use since the Republican Army, so shy does he imply the name change.?

According Arrianus (he describes the Legion of Hadrianus +/- 120/130AD) the soldiers had carried just one spear
kontos in the meaning of the pilum - it was the weapon of the first rank.
The rear rank of lonchophoroi were equipped with the lancea.
Arrianou ektaxis kata Alanon
[...]pro ton akontiston tous hoplitas[...]
[...]kai lonchas hoi lonchophoroi akontizetosan hoi te psiloi kai hoi thyreophoroi[...]

In Vegetius every man in the first 5 Cohors was equipped now with 2 pila - but when he comes to the second line he just say that they (the soldiers) were equipped in a "similar way". Perhaps the lancea was still in use - at least an interesting note as suggested in Vegetius Liber III XIIII
[...]Instructionis lex est, ut in primo exercitati et ueteres milites conlocentur, quos antea principes uocabant, in secundo ordine circumdati catafractis sagittarii et optimi milites cum spiculis uel lanceis ordinentur, quos prius hastatos uocabant. [...]

So, it is in my opinion important to check certain elements of Vegetius` report isolated from the rest.
It is also interesting to note that he sometimes tells the reader that he knows something, - another time he say "this was so and so - as it is teached (today)...".

Don't know much about Arrian and the Strategikon, haven't managed to acquire a copy.

I believe you said in your original thread that he was referencing the Second line as to carrying Lancaea as the Govenor of Cappadocia (Can't Remember his name) did in his encounter with the Sarmatae in the 2nd century (141 I believe). Judging by the name Lanciarii I would also presume the Lancea/Verutum (Doesn't matter as both were three-sided javelins as described by Vegetius Above) was still in use by skirmisher units such as the Lanciarii and Exculcatores.